Dissertations / Theses on the topic 'Surface ball'
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Hoehner, Steven Douglas. "The Surface Area Deviation of the Euclidean Ball and a Polytope." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1459355790.
Full textJafri, Syed M. "Modeling of impact dynamics of tennis ball with a flat surface." Thesis, Texas A&M University, 2003. http://hdl.handle.net/1969.1/2441.
Full textJerez, Mesa Ramon. "Study and characterisation of surface integrity modification after ultrasonic vibration-assisted ball burnishing." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30024/document.
Full textThis dissertation is an experimental research project into the mechanical effects of the ultrasonic vibration-assisted ball burnishing process on the surface integrity of surfaces machined through ball-end milling. Due to the lack of commercial tools able to perform this process, the study includes firstly the design and characterisation of a prototype to that effect. An experimental analysis is then undertaken, applying the process to AISI 1038 and Ti-6Al-4V surfaces of high industrial and aeronautical value. The experimental campaign is designed based on a Taguchi orthogonal array that includes five factors, namely: preload, number of passes, feed velocity, strategy and initial surface texture. Results are analysed in terms of topological characteristics, residual stress and hardness, in order to identify and understand the impact of process parameters on surface integrity, to define the best parameters for performing the process and to assess the positive effects caused by the introduction of vibrations as a means of assistance. Results reveal that the initial texture is the most influential parameter on all outcomes. Texture results show that the vibrations can enhance the roughness and texture results, as long as they have sufficient low initial amplitude. Furthermore, only the preload and number of passes influence the results, with a pair of values being found in all cases that serve a threshold from which further plastic strain is detrimental for the final surface topology. In terms of residual stress, all parameters are influential in the results, especially the burnishing strategy, through which a certain component of the residual stress tensor can be adequately reinforced. Finally, the burnishing operation proves to modify the hardness of deep layers down to 0.5 mm, applying the vibration-assisted process. The main conclusion is that the optimal parameters for performing the process are different with regards to the optimisation objective. Some useful combinations are proposed for performing the process depending on the desired target
Yen, Yung-Chang. "Modeling of metal cutting and ball burnishing prediction of tool wear and surface properties /." Columbus, Ohio : Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1073065455.
Full textTitle from first page of PDF file. Document formatted into pages; contains xxviii, 254 p.; also includes graphics. Includes abstract and vita. Advisor: Taylan Altan, Dept. of Industrial and Systems Engineering. Includes bibliographical references (p. 240-248).
Jerez, Mesa Ramón. "Study and characterisation of surface integrity modification after ultrasonic vibration-assisted ball burnishing." Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/668792.
Full textEsta tesis es un estudio experimental que versa sobre los efectos del proceso de bruñido con bola asistido por vibraciones ultrasónicas sobre la integridad superficial de superficies mecanizadas mediante fresa hemisférica. Dada la indisponibilidad de herramientas comerciales capaces de efectuar este proceso, el estudio incluye en primer lugar el diseño y caracterización de un prototipo a tal efecto. Posteriormente, se realiza un análisis experimental aplicando el proceso sobre superficies de dos aleaciones de interés industrial y aeronáutico, AISI 1038 y Ti-6Al-4V, siguiendo un diseño de experimentos fraccionario basado en una matriz ortogonal de Taguchi. Para ello, cinco factores son incluidos en el modelo, a saber: la precarga, el número de pasadas, la velocidad de avance, la estrategia de bruñido, y la textura de la superficie de partida. Los resultados se evalúan en términos de textura, tensiones residuales y dureza, para identificar y comprender el impacto de este proceso y de sus parámetros de operación sobre la integridad superficial, para definir los mejores parámetros a aplicar para cada material, y con el fin de evaluar los efectos positivos provocados por la introducción de las vibraciones como medio de asistencia. Los resultados revelan que la textura inicial es el parámetro que define en mayor medida el estado de las superficies finales. Los resultados de textura evidencian que las vibraciones pueden mejorar en mayor medida la topología de las superficies objetivo, siempre que éstas sean suficientemente finas. Además, sólo la precarga y el número de pasadas influyen en el resultado, encontrando en todo caso un par de valores limítrofe a partir del cual las superficies se ven dañadas. Los resultados de tensiones residuales muestran que todos los parámetros son influyentes en el resultado final, especialmente la estrategia de bruñido, con la que puede modificarse la dirección preferencial del tensor de tensiones superficial. Finalmente, el bruñido demuestra modificar la dureza positivamente hasta capas de aproximadamente 0,5 mm, aplicando el proceso asistido con vibraciones. Se concluye que los parámetros óptimos de proceso son diferentes en función del objetivo de optimización, y deben definirse en base a dos variables de partida: el material objetivo y la textura que éste presenta antes del proceso.
Cette thèse étudie les effets du processus de brunissage à bille assisté par vibrations ultrasoniques sur l’intégrité surface des surfaces usinées par fraisage hémisphérique. Compte tenu de l’inexistence d’outils commerciaux capables de réaliser ce processus, l’étude débute par la conception et la caractérisation d’un prototype capable de l’exécuter. Par la suite, une analyse expérimentale est menée, en utilisant le procédé sur les surfaces de deux alliages d’intérêt industriel et aéronautique, AISI 1038 et Ti- 6Al-4V. Pour cela, un plan d’expériences est elaboré à base d’une matrice orthogonale Taguchi. Cinq facteurs sont inclus dans le modèle : la précharge, le nombre de passes, la vitesse d’avance, la stratégie de brunissage et la texture initiale de la surface préalablement usinée. Les résultats sont évalués en termes de texture finale, de contrainte résiduelle et de dureté, pour identifier et comprendre l’impact de ce procédé et des paramètres opératoires sur l’intégrité de surface, pour définir les meilleurs paramètres à appliquer pour chaque matériau, et pour évaluer les effets positifs provoqués par l’introduction de vibrations comme moyen d’assistance. Pour cela, la notion d’intégrité de surface est rappelée, voire redéfinie dans le cas de la texture de surface. En effet, les critères classiquement utilisés se révèlent inaptes à caractériser les surfaces obtenues, et une nouvelle méthodologie d’analyse des topologies de surface est proposée. Les résultats obtenus suite à la réalisation du plan d’expériences révèlent que la texture initiale est le paramètre prépondérant. Les résultats de la topologie de surface montrent que les vibrations peuvent améliorer la rugosité et la texture des surfaces dans la mesure où l’état de surface initial est sufisamment fin. Ensuite, seule la précharge et le nombre de passes influencent le résultat, avec, dans tous les cas, un couple de valeurs limites à partir desquelles les surfaces sont endommagées. Les résultats des contraintes résiduelles montrent que tous les paramètres influent sur le résultat final, en particulier la stratégie de brunissage, avec laquelle la direction préférentielle du tenseur de la contrainte superficielle peut être modifiée. Enfin, le brunissage montre une modification positive de la dureté à des couches d’environ 0,5 mm en appliquant le processus assisté avec vibrations. Nous concluons que les paramètres de processus optimaux sont diférents en fonction de l’objectif d’optimisation, et que certaines combinaisons peuvent être utiles en fonction de ces objectifs.
Aquesta tesi és un estudi experimental que tracta sobre els efectes del procés de brunyit amb bola assistit per vibracions ultrasòniques sobre la integritat superficial de superfícies mecanitzades amb fresa hemisfèrica. Degut a la indisponiblitat d’eines comercials capaces d’aplicar aquest procés, l’estudi inclou en primer lloc el disseny i la caracterització d’un prototip capa d’executar-lo. Posteriorment, es realitza una anàlisi experimental aplicant el procés sobre superfícies de dues aliatges d’internes industrial i aeronàutic, AISI 1038 i Ti-6Al-4V, seguint un disseny d’experiments basat en una matriu ortogonal Taguchi. Per això, cinc factors són inclous en el model: la precàrrega, el nombre de passades, la velocitat d’avenç, l’estratègia de brunyit i la textura de la superfície inicial. Els resultats s’avaluen en termes de textura final, tensions residuals i duresa, per identificar i comprendre l’impacte d’aquest procés i dels seus paràmetres d’operació sobre la integritat superficial, definir els millors paràmetres a aplicar per a cada material, i amb l’objectiu d’avaluar els efectes positius provocats per la introducció de les vibracions com a mitjà d’assistència. Els resultats evidencien que la textura inicial és el paràmetre que defineix en major mesura l’estat de les superfícies finals. Els resultats de textura indiquen que les vibracions poden millorar en major mesura la rugositat i textura de les superfícies, sempre que aquestes siguin suficientment fines. A més, només la precàrrega i el nombre de passades influeixen sobre el resultat, trobant en tot cas un parell de valors límits a partir del qual les superfícies són empitjorades. Els resultats de tensions residuals mostren que tots els paràmetres són influents sobre el resultat final, especialment l’estratègia, amb la què es pot millorar la direcció preferencial del tensor de tensions superficial. Finalment, el brunyit demostra modificar la duresa positivament fins a capes d’aproximadament 0.5 mm de profunditat, aplicant el procés assistit amb vibracions. Es conclou que els paràmetres òptims de procés són diferents en funció de l’objectiu d’optimització, i es proposen algunes combinacions que poden ser útils en funció del mateix.
Lim, Ee Meng. "The prediction of dimensional errors and machining planning for sculptured surface productions using ball-end milling /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487862399449007.
Full textAlgarin, Paula C. "Effects of Zn Doping and High Energy Ball Milling on the Photocatalytic Properties of TiO2." [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002462.
Full textCug, Mutlu. "Effects Of Swiss Ball Training On Knee Joint Reposition Sense, Core Strength And Dynamic Balance In Sedentary Collegiate Students." Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614041/index.pdf.
Full textVenturini, Chiara. "On-surface coupling reactions on calcium carbonate." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30158/document.
Full textCovalent coupling on metallic surfaces in UHV (Ultra High Vacuum) conditions is a new method for preparing molecular structures otherwise impossible to achieve in solution (graphene nanoribbons, 2D polymers for instance). The major challenge is now to extend these reactions from metallic to insulating surfaces, for future applications as, for instance, in molecular electronics. In particular, the coupling reaction of benzoic acid derivatives, grafted on calcite via carboxylic groups, has been demonstrated for the first time in UHV conditions. In the first part of this work, we synthesized precursor molecules for specific reactions (homocoupling of ethynes, photopolymerization, polycondensation and Ullmann reaction) on calcium carbonate in UHV conditions. In the second part of this work we extended this investigation up to the macroscale level (semi-preparative) by grafting molecules on calcium carbonate microparticles, followed by reaction activation and finally by dissolution of the substrate in order to recover the coupling products. The calcium carbonate microparticles were prepared by grinding commercial product or by spray pyrolysis and were fully characterized by FTIR, TG/DTG, XRD, SEM and BET techniques. Then, after grafting of organic reactant, the reactions were activated with two different solvent-free methods: by grinding in a planetary milling machine or by heating the samples in a furnace under vacuum. Whereas in UHV conditions, 4-iodobenzoic acid affords biphenyldicarboxylic acid, mechanochemical condition gives benzoic acid and thermal activation the dibenzoic acid ether
Nakazawa, Takeshi. "THREE-DIMENSIONAL NON-CONTACT SURFACE PROFILERS FOR SEMICONDUCTOR IC PACKAGE INSPECTION." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/205472.
Full textBiscolla, Laura Maria da Cunha Canto Oliva. ""Controlabilidade do rolamento de uma esfera sobre uma superfície de revolução"." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/45/45132/tde-31072006-141249/.
Full textThis work starts by presenting the classical concepts of rolling (without slipping and without slipping or twisting) of a surface over another one, using the Darboux referential frames of the two surfaces along their contact curves. It shows the equivalence between these concepts with other definitions. In the sequel one studies the controllability in the rolling problem of a ball over a surface of revolution S, including both: the non slipping and the non slipping or twisting cases; controllability aims to determine the reachability between two 'states'of the ball (position on S and orientation), that is, two elements of the configuration space S × SO(3). It follows by establishing conditions on controls in order that the rollings occur along geodesics of S and by studying the controllability in this situation. Finally, it is shown that if S is the plane, 3 or 4 retilinear moves without slipping or twisting are enough to guarantee reachability between two states of the ball.
Bukhari, Sarfaraz. "Evaluation of the effects of processing conditions on shear strength in Pb-free surface mount assembly." Diss., Online access via UMI:, 2004. http://wwwlib.umi.com/dissertations/fullcit/1422361.
Full textAlsairafi, Abdullah Issa. "Numerical and Experimental Investigation of the Manufacturing Process of Ball BearingsFocusing on Enhancing the Aesthetics of the Outer Surface by Removing the ShiningBand." Youngstown State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1527013271365695.
Full textSouto-Lebel, Aurélien. "Rôle de l’intégrité de surface dans la tenue en fatigue d’un acier bainitique après fraisage de finition." Thesis, Cachan, Ecole normale supérieure, 2014. http://www.theses.fr/2014DENS0028/document.
Full textThis thesis focuses on the effects of finishing milling on fatigue damage. Machining processes such as milling are known to incur high thermomechanical loadings, which alter the geometrical (roughness) and mechanical (residual stresses, strain hardening) properties of the surface and sub-surface of produced parts. These properties, designated as surface integrity, are likely to affect significantly the fatigue strength of machined parts. The problem has been studied here in the case of the ball-end tool finishing milling of bainitic steels. Several approaches were followed, starting with the measurement and characterization of surface integrity, and especially of its anisotropic nature. Secondly, the role played by surface integrity during fatigue behaviour was highlighted through a bending test campaign including different surface types. These mainly empirical works were completed with the study and improvement of a hybrid approach aiming at combining experimental data and modelling in order to predict quickly and efficiently the residual stress profiles induced by the process. Finally, the last part of the study has dealt with taking account of the results thus obtained in a so-called two-scale damage model, in order to describe, and insofar as possible, to predict the fatigue behaviour of the machined material
Ткаченко, С. М., Володимир Іванович Савчук, Владимир Иванович Савчук, and Volodymyr Ivanovych Savchuk. "Шляхи зниження шорсткості виконавчих поверхонь гвинтів кульових кранів на оздоблювальному етапі їх обробки." Thesis, Сумський державний університет, 2018. http://essuir.sumdu.edu.ua/handle/123456789/67377.
Full textTumne, Pushkraj Satish. "Investigation of bulk solder and intermetallic failures in PB free BGA by joint level testing." Diss., Online access via UMI:, 2009.
Find full textIncludes bibliographical references.
Majeed, Sulman. "Rework & reliability of area array components." Diss., Online access via UMI:, 2009.
Find full textIncludes bibliographical references.
Robinson, Fiona. "Approaches to Understanding the Milling Outcomes of Pharmaceutical Polymorphs, Salts and Cocrystals. The Effect of Different Milling Techniques (Ball and Jet) on the Physical Nature and Surface Energetics of Different Forms of Indomethacin and Sulfathiazole to Include Computational Insights." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5412.
Full textCotton, Ross Thomas. "Surface interactions of soccer balls." Thesis, Loughborough University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.536210.
Full textGuillemot, Nicolas. "Prise en compte de l'intégrité de surface pour la prévision de la tenue en fatigue de pièces usinées en fraisage." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2010. http://tel.archives-ouvertes.fr/tel-00610030.
Full textCordingley, Leon Paul. "Advanced modelling of surface impacts from hollow sports balls." Thesis, Loughborough University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247898.
Full textГончар, Кирило Романович. "Високотемпературна нітроцементація цирконію." Bachelor's thesis, КПІ ім. Ігоря Сікорського, 2019. https://ela.kpi.ua/handle/123456789/28151.
Full textIn this work the possibility of simul-taneous saturation of zirconium in products of decomposition of am-monium oxalate has been investigat-ed. The ratio of components of the equi-librium composition of the reaction medium to the application of com-plex coatings by diffusion saturation with nitrogen, carbon and oxygen with the participation of hydrogen has been theoretically calculated and experimentally confirmed. The com-position of both the gas and the con-densed phase depends on the com-position and ratio of reagents in the saturated mixture . Calculated reaction formation nitride ZrN, oxide ZrO2, zirconium carbide ZrC with hydrogen and the reaction between each of nitrogen, oxygen, carbon and hydrogen. Thermody-namic probability of formation of carbides, nitrides and oxides decreas-es with increasing temperature;
Paracha, Omair I. "Surface Characterization of Cricket Balls Using Area-scale Fractal Analysis." Digital WPI, 2010. https://digitalcommons.wpi.edu/etd-theses/103.
Full textBuřival, Tomáš. "Opravy DPS s BGA a FC pouzdry." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-217906.
Full textDignall, Richard John. "Modelling the impact of tennis balls on court surfaces." Thesis, University of Sheffield, 2005. http://etheses.whiterose.ac.uk/14607/.
Full textMaurel, Pierre. "Déformation plastique sévère des surfaces d’alliages à faible densité par grenaillage ultrasonique : gradients de microstructures, comportements en fatigue et en tribologie." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0182.
Full textThe impact of ultrasonic shot peening on titanium and aluminium alloys is studied at room temperature and at cryogenic temperature. This process may also be called surface mechanical attrition treatment (SMAT). Fatigue strength and tribological behaviour are investigated in order to better understand the pros and cons of this process. Two titanium alloys were chosen: pure titanium in its fully α form and β-metastable titanium in its fully β form. This choice makes it possible to correlate the influence of the initial microstructure on the treatment of severe plastic deformation and on the final properties. The β-metastable titanium is sensitive to strain-induced martensitic transformation, which allows exploring the possibility of introducing martensite to the shot-peened surface to delay, for example, short crack propagation in fatigue testing. Shot peening at cryogenic temperature in this case improves the initiation of the martensitic transformation. In addition to facilitating martensitic transformation, cryogenic temperature shot peening increases the yield strength of alloys during processing, which has the effect of reducing the flow of material at the shot-peened surface. Thereby, it improves surface integrity and changes tribological and fatigue properties. Two precipitation hardenable aluminum alloys were also studied: 2024 and 7075. The purpose of this aluminium study is to compare the impact of ultrasonic shot blasting when used before or after precipitation aging. As the dislocations produced during ultrasonic shot-peening serve as preferential nucleation sites, the objective is to explore the possibility of improving (e.g. in terms of hardness) the precipitation aging by refining the size of the precipitates and increasing their density. The use of two series of aluminium should make it possible to compare the effect of the treatment on the two different alloying compositions. In addition, these two alloys show significant differences in terms of defect sensitivity, permitting to study the impact of surface integrity after ultrasonic shot-peening on mechanical properties. The study of tribological and fatigue behaviour allows to conclude about the effectiveness of these treatments under common conditions of use
Kučera, Lukáš. "Smáčení a roztékání roztavené pájky po kovovém povrchu." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218735.
Full textTran, Thi Phuong Thao. "Développement de biocomposites à base de Poly(Acide Lactique) et de balles céréalières : vieillissement des biocomposites et traitement de surface des balles." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20203/document.
Full textThe cereal husks, namely the envelope around the grain, have recently attracted the attention of scientists for biocomposites development, because they are low-cost, renewable, biodegradable, and available in abundant volume throughout the world. Their chemical composition and their thermal and mechanical properties are similar to the natural fibers.In this work, two types of rice husk and two types of Einkorn wheat husk were studied through their microstructure, chemical composition, mechanical and thermal properties. The husks have been incorporated into a bio-sourced and biodegradable matrix, namely poly (lactic acid) (PLA) to produce biocomposite which functional properties were studied. It appears that the husks can be good candidates for strengthening the PLA through improved adhesion at the interface between the husks and the PLA.To improve the husks/PLA interface, the husks were treated with an alkaline solution (NaOH) and organosilane coupling agents, such as 3-aminopropyltriethoxysilane and 3 - glycidoxypropyltrimethoxysilane. The alkaline treatment has removed much of hemicelluloses, lignin, wax and silica present in the husks. The dissolution of these components resulted in a higher hygroscopicity of husks and lower mechanical properties of biocomposites. The coupling between an alkaline treatment and a silane treatment seems to provide better properties than the silane treatment alone. This surface treatment has a greater impact on the Einkorn wheat husks than on rice husksThe variations of the functional properties of rice husks based biocomposites during different ageings (thermal ageing, hydro-thermal ageing, hygro-thermal cycled ageing, UV ageing) was studied. The results show that the microstructural changes induced by ageing significantly influence the properties of biocomposites. Biocomposites degradation results in a decrease of the average molecular weight of PLA. The reorganization of these macromolecules significantly increases the degree of crystallinity of the material. This causes a change in color, dimensional stability of devices and mechanical properties of PLA and biocomposites which essentially depends on the ageing temperature regards to the glass transition temperature of PLA. It appears that the addition of husks accelerates the degradation of PLA. In the case of a hydro-thermal ageing performed above the glass transition temperature of the PLA, a reduction of this degradation was demonstrated by the use of specific surface treatments of husks
Latza, Victoria Maria [Verfasser], Ilko [Akademischer Betreuer] Bald, Emanuel [Akademischer Betreuer] Schneck, Ilko [Gutachter] Bald, Emanuel [Gutachter] Schneck, and Aleksandra [Gutachter] Szcześ. "Interactions involving lipid-based surfaces : from protein adsorption to membrane adhesion / Victoria Maria Latza ; Gutachter: Ilko Bald, Emanuel Schneck, Aleksandra Szcześ ; Ilko Bald, Emanuel Schneck." Potsdam : Universität Potsdam, 2020. http://d-nb.info/1219578819/34.
Full textSarhan, Radwan Mohamed [Verfasser], Matias [Akademischer Betreuer] Bargheer, Sebastian [Akademischer Betreuer] Schlücker, and Ilko [Akademischer Betreuer] Bald. "Plasmon-driven photocatalytic reactions monitored by surface-enhanced Raman spectroscopy / Radwan Mohamed Sarhan ; Matias Bargheer, Sebastian Schlücker, Ilko Bald." Potsdam : Universität Potsdam, 2019. http://d-nb.info/1218405066/34.
Full textHadáček, Milan. "Design výukové konzole." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-227907.
Full textMukherjee, Puri P. "Investigations on monoclonal auto-antibodies directed against the Thy-1 surface antigens isolated from Balb/c mice infected with Trypanosoma brucei." Thesis, Brunel University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377810.
Full textAndersson, Henrik. "Yt- och strukturpåverkan vid finfräsning av härdat verktygsstål." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-51787.
Full textIn this thesis, investigations on hardened finish milled surfaces was done in collaboration with the tool steel manufacturer Uddeholms AB in Hagfors, Sweden. The steel material is affected by machining operations, sometimes in a negative destructive manner. An experimental test series containing a total of 90 surfaces in hot work steels Uddeholm Orvar Supreme and Uddeholm Dievar were milled, measured and evaluated to clarify the milling operations effect on the steels mechanical properties. It was found that the material is affected differently according to how the milling was preformed and with which type of milling tool. In this thesis, only solid carbide end-radius milling tools were used. The surface analysis were conducted with a range of measuring techniques including optical surface roughness measurements, hardness measurements in Vickers scale, residual stress measurements with X-ray diffraction (XRD) and microstructural analysis with optical light microscope. These measurements were conducted in order to determine the milling operations mechanical affects and grade of alteration of the tool steels surfaces. In the least favorable cases, the effect from machining are so profound, that degradation of produced components can be expected in terms of fatigue wear resistance. The goal of the thesis is to identify the most favorable process parameters, in order to minimize degradation of the tooling material in customer user cases, together with the opportunity to give fact based advice to Uddeholms AB customers on the most favorable process parameters in finish milling with radius-mills of hardened hot work tool steels. In this way the customer can utilize the tooling material at its full potential.
Prinz, Julia [Verfasser], Ilko [Akademischer Betreuer] Bald, Tim [Gutachter] Liedl, and Michael Uwe [Gutachter] Kumke. "DNA origami substrates as a versatile tool for surface-enhanced Raman scattering (SERS) / Julia Prinz ; Gutachter: Tim Liedl, Michael Uwe Kumke ; Betreuer: Ilko Bald." Potsdam : Universität Potsdam, 2017. http://d-nb.info/1218793171/34.
Full textPETOUR, PASCAL. "Isolement et identification de nouveaux epitopes exprimes en surface de l'hepatocyte infecte par des plasmodies : modele de la souris balb/c infectee par plasmodium yoelii." Paris 6, 1997. http://www.theses.fr/1997PA066503.
Full textPonthus, Nicolas. "Contact sec glisssant sous faible charge : de la topographie des surfaces à la dynamique des solides de l'interface." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEC021/document.
Full textThis PhD thesis addresses the issue of the dynamics, normal to the interface, of a dry steady-sliding contact between two random topographies under weak normal load. In this context, the motion of a slider under its own weight has been studied experimentally. Measurements, using a laser vibrometer, of the normal displacement and velocity of the slider confirm the existence of a transition, as the sliding speed increases, from a regime of permanent contact to a regime of lift-offs, shocks and rebounds.At low speed, the normal motion is due to a geometrical filtering of the topographies, the statistical and spectral properties of which have been described. The roles of the roughness, including its spectral breadth and correlation length, and of the apparent contact area have been identified and analyzed. Those results have been reproduced not only using numerical models, but also using analytical ones based on the extreme value theory. Bouncing-Ball-like models, the excitation of which is assumed to be given by the geometrical filtering, have also been implemented and match with a broad range of experimental observations in dynamical regime, from the transition to vibro-impacts.To test some of the hypothesis of the models, a new experimental multi-channel slider has been designed and has enabled access to the spatial localization of the transient micro-contacts between the antagonists surfaces. It has been shown that micro-contacts are governed by a characteristic length at low sliding speed and by a characteristic time at high speed. The rotational motion of the slider also increases with sliding speed, changing the micro-contact distribution along the surface of the slider
Ciminelli, Jennifer M. "A GIS and Remote Sensing Based Analysis of Impervious Surface Influences on Bald Eagle (Haliaeetus leucocephalus) Nest Presence in the Virginia Portion of the Chesapeake Bay." VCU Scholars Compass, 2006. http://hdl.handle.net/10156/1928.
Full textKaram, Steve. "Croissance du volume des boules dans les revêtements universels des graphes et des surfaces." Phd thesis, Université François Rabelais - Tours, 2013. http://tel.archives-ouvertes.fr/tel-00914945.
Full textDalphin, Jérémy. "Étude de fonctionnelles géométriques dépendant de la courbure par des méthodes d'optimisation de formes. Applications aux fonctionnelles de Willmore et Canham-Helfrich." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0167/document.
Full textIn biology, when a large amount of phospholipids is inserted in aqueous media, they immediatly gather in pairs to form bilayers also called vesicles. In 1973, Helfrich suggested a simple model to characterize the shapes of vesicles. Imposing the area of the bilayer and the volume of fluid it contains, their shape is minimizing a free-Bending energy involving geometric quantities like curvature, and also a spontanuous curvature measuring the asymmetry between the two layers. Red blood cells are typical examples of vesicles on which is fixed a network of proteins playing the role of a skeleton inside the membrane. One of the main work of this thesis is to introduce and study a uniform ball condition, in particular to model the effects of the skeleton. First, we minimize the Helfrich energy without constraint then with an area constraint. The case of zero spontaneous curvature is known as the Willmore energy. Since the sphere is the global minimizer of the Willmore energy, it is a good candidate to be a minimizer of the Helfrich energy among surfaces of prescribed area. Our first main contribution in this thesis was to study its optimality. We show that apart from a specific interval of parameters, the sphere is no more a global minimizer, neither a local minimizer. However, it is always a critical point. Then, in the specific case of membranes with negative spontaneous curvature, one can wonder whether the minimization of the Helfrich energy with an area constraint can be done by minimizing individually each term. This leads us to minimize total mean curvature with prescribed area and to determine if the sphere is a solution to this problem. We show that it is the case in the class of axisymmetric axiconvex surfaces but that it does not hold true in the general case. Finally, considering both area and volume constraints, the minimizer cannot be the sphere, which is no more admissible. Using the shape optimization point of view, the third main and most important contribution of this thesis is to introduce a more reasonable class of surfaces, in which the existence of an enough regular minimizer is ensured for general functionals and constraints involving the first- and second-Order geometric properties of surfaces. Inspired by what Chenais did in 1975 when she considered the uniform cone property, we consider surfaces satisfying a uniform ball condition. We first study purely geometric functionals then we allow a dependence through the solution of some second-Order elliptic boundary value problems posed on the inner domain enclosed by the shape
Hsiung, Daniel. "REDESIGN OF A TRIBOLOGICAL TEST MACHINE." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Maskinteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-29571.
Full textBaštek, Jozef. "Modelování a zobrazování pomocí blobů." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2011. http://www.nusl.cz/ntk/nusl-237054.
Full textJaouen, Kévin. "Backside absorbing layer microscopy : a new tool for the investigation of 2D materials." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS296/document.
Full textOptical microscopy based on anti-reflective coatings is a simple yet powerful characterization tool which notably allowed the first observation of graphene in 2004. Since then, the field of two-dimensional (2D) materials has developed rapidly both at the fundamental and applied levels. These ultrathin materials present inhomogeneities (edges, grain boundaries, multilayers, etc.) which strongly impact their physical and chemical properties. Thus their local characterization is essential. This thesis focuses on a recent enhanced-contrast optical microscopy technique, named BALM, based on ultrathin (2-5 nm) and strongly light-absorbing (metallic) anti-reflective layers. The goal is notably to evaluate the benefits of this technique for the study of 2D materials and their chemical reactivity. The various levers to improve 2D materials observation were investigated and optimized for two model materials: graphene oxide and MoS₂ monolayers. The investigation of molecular layer deposition dynamic notably showed the extreme sensitivity of BALM for such measurements and the significant contribution of multilayers anti-reflective coatings to enhance contrast during the observation of 2D materials. One of the main assets of BALM comes from its combination to other techniques. We particularly considered the coupling between optical measurements and electrochemistry for which the anti-reflective layer serves as working electrode. We investigated optically the dynamic of electrochemical reduction of Graphene Oxide (GO), the electrografting of organic layers by diazonium salts reduction on GO and its reduced form (rGO), as well as the intercalation of metallic ions within GO sheets. By combining versatility and high-contrast, BALM is established as a promising tool for the study of 2D materials, especially for the local and in situ characterization of their chemical and electrochemical reactivity
Debeauquesne, Diane. "Analyse des différentes formes sociales de pratiques physiques et sportives sur sable : Regard singulier sur quatre pratiques et leurs pratiquants : le beach volley, le beach tennis, le beach rugby et le char à voile." Thesis, Paris 5, 2012. http://www.theses.fr/2012PA05L003.
Full textPas de résumé en anglais
Simms, Amy Nicole. "Examination of Neisseria gonorrhoeae opacity protein expression during experimental murine genital tract infection /." Download the dissertation in PDF, 2005. http://www.lrc.usuhs.mil/dissertations/pdf/Simms2005.pdf.
Full textWang, Wei-Jei, and 王偉杰. "Surface Inspection System for Miniature Steel Ball." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/nn847q.
Full text國立臺北科技大學
工業工程與管理研究所
103
Precision ball are mainly used in precision bearings precision industrial manufacturing. A good quality ball determines the life of machinery and equipment, the surface defects also become the need of sophisticated detection products. There are dishing the ball blemishes, scratches, rust and metal fatigue cracking or ball-body aircraft due to minute and a ball-type structure, for minor surface defects not easily detected, so this study use a camera to capture images continuously to detect the missing rate lower. The main purpose of this study on precision ball machine vision for analysis and detection of surface defects. Ball has more two-dimensional plane, the use of the detection camera to take more images, processing techniques to distinguish defects image enhancement features, and includes circuit integration, access to materials of the bodies and institutions in order to complete the entire ball detection system by a smaller hardware equipment.
Lu, Chien-Hsing, and 呂建興. "Analysis of Surface Roughness for Ball-End Milling." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/49287011008746817972.
Full text逢甲大學
機械工程學所
100
Surface roughness is one of the most important performance indices for precision machining. This thesis presents an analysis on the effects of cutting parameters on surface roughness in ball-end milling process. The surface roughness in both feed direction and transverse direction is investigated. The cutting parameters include the feed, the spindle speed, the path interval, and the angle between the surface normal and the tool axis. In the study, 13 and 19 sets of data are conducted to establish empirical models for surface roughness in the feed and the transverse directions, respectively. Based on the proposed model, we can predict the surface roughness, design the tool paths and cutting parameters, and consequently, improve the machining quality and efficiency.
Lee, Yi-Cheng, and 李易澂. "Modeling of Surface Roughness for Ball-Milling S304." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/98924517709775004302.
Full text逢甲大學
機械與電腦輔助工程學系
104
This thesis presents an analysis on the effects of machining parameters on surface roughness in ball-end milling stainless steel S304, and thereby develops an experimental model. In the study, a Taguchi L8 table is first utilized to determine the dominant cutting parameters (that are feed, spindle speed, and path interval), and thereby the roughness models in the feed and the transverse directions are developed, respectively. Moreover, two different sets of cutting experiments with different-sized cutters (of which radii are 5 mm and 3 mm, respectively) are conducted to obtain the corresponding models, and consequently, the effect of cutter size is analyzed. Based on the proposed surface-roughness model, we can accurately describe and predict the surface roughness of machined part, and thereby, improve the machining accuracy and efficiency.
Chang, Yu-Jui, and 張祐睿. "CNC Machine Tool Surface Interpolator for Ball-End Milling of Free-Form Surfaces." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/86530668672143431693.
Full text逢甲大學
機械工程學系
88
Because of so many problems in the traditional CNC machine tool interpolator design, this paper presents a new type of it that is capable of generating the cutter path for ball-end milling of a free-form surface. The surface interpolator comprises three major points as follows: On-line algorithms for cutter-contact CC path scheduling, CC path interpolator, and tool offsetting. There are three kinds of interpolator algorithms, iso-parametric, iso-scallop and iso-planar respectively. The proposed surface interpolator gains the advantages for minimizing the data feeding to the CNC machine tool and maintaining the desired feedrate and more position accuracy along the CC path.
HSU, CHAO-CHIN, and 許朝欽. "Modeling of Surface Roughness for Ball-Milling S45-C." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/59663558526229045936.
Full text逢甲大學
機械與電腦輔助工程學系
104
This thesis presents an analysis on the effects of machining parameters on surface roughness in ball-end milling medium carbon steel S45-C, and thereby develops an experimental model. In the study, a Taguchi L8 table is first utilized to determine the dominant cutting parameters (that are feed, spindle speed, and path interval), and thereby the roughness models in the feed and the transverse directions are developed, respectively. In addition, the analyses of different parameter ranges and different machine tools are conducted. Based on the proposed surface-roughness model, we can accurately describe the surface roughness in ball-ended milling, and thereby, improve the machining accuracy and efficiency.
Chang, Chin-i., and 張進一. "Improvement A Solder Ball of Surface Mount Technology Process." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/63101989138473369623.
Full text國立雲林科技大學
工業工程與管理研究所碩士班
99
In the era of rapid technological advances, consumers have increasingly demanding for products. Therefore, electronic products become shorter, smaller, lighter and thinner to fit various requirements. From history of surface Mount Technology, it has been early developed by the Japanese industries and then applied to the production process of electronic products largely. So far, in response to the diversification of products and reduce the cost of cases, Surface Mount Technology has continued to pursue breakthrough, in order to seek more precision and productivity. However, surface mount manufacturing process has not only includes equipments, also raw materials and other related conditions. Therefore, the production process is full of many uncertain variables in combination, How to troubleshoot and analyze many of variables, to reduce product defect rate and improve production efficiency, which is the subject of concern to the electronics industry. The research aims to investigate the abnormity of solder ball in production process, and select the four factors from Cause-effect diagram to study this problem. The four factors are stencil design, mount height correction, squeegee force and different maker of solder paste, and using Design of Experiment and Minitab software to analysis data. The results of the study could be applied into the actual production, which would ensure against the abnormity of solder ball and further improve product quality.