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Abstract Prediction of chip-breaking in machining is an important task for automated manufacturing. There are chip-breaking limits in machining chip-breaking chart, which determine the chip-breaking range. This thesis presents a study of the effect of 3-D groove insert parameters on chip breaking chart. Based on the chip-breaking criteria, the critical feed rate is formulated through an analysis of up-curl chip formation for 3-D grooves. Also in order to predict chip-breaking limits, for protruded insert grooves in finish machining, analytical models are established. In the analytical models, minimum and maximum depth of cut are identified for using different chip breaking models. As well insert nose radius effects on chip thickness for small depth of cut are studied. In the end, the analytical critical feed rate model is extended to finish machining with 3-D chipbreaking grooves.

Master of Science / Department of Animal Sciences and Industry / Jeffrey S. Stevenson / Our objective was to determine the optimal time to inseminate artificially cows following the standard CO-Synch protocol that also included a progesterone-releasing intravaginal controlled internal drug release (CIDR) insert. Lactating females from 3 Kansas locations were utilized. Crossbred Angus cows (n = 212) from the Agriculture Research Center in Hays (ARCH; location 1); Angus-Hereford crossbred cows (n = 249) from the Kansas State University Cow-Calf Unit (location 2); and purebred Angus, Hereford, and Simmental cows (n = 144) from the Kansas State University Purebred Beef Unit (location 3) were used in this study. Cows within each location were blocked by parity and assigned randomly within blocks to be artificially inseminated (AI) at 4 different times after the PGF2[Alpha] injection of the protocol: 48, 56, 64, or 72 h. Pregnancy diagnosis occurred at 32 and 63 d after insemination. Blood samples were collected 9 to 10 d and just before the first GnRH injection. Radioimmunoassays were performed on the blood sera samples to determine progesterone concentrations. Progesterone concentrations determined that approximately 60% of cows were cycling at the initiation of the study. A difference in cyclicity was observed with regards to age as well as body condition score. Pregnancies per AI (P/AI) at d 32 varied according to location and cycling status. Pregnancy loss between d 32 and 63 also was greatest for cows inseminated at 48 and 72 h. As pregnancy rates at d 63 increased with the 56- and 64-h treatments, pregnancy loss decreased. A significant difference in calving interval was detected among treatments, the shortest calving interval at 56 h. Results indicated that in most situations, the 56- and 64-h treatments presented the most desirable outcomes. The 56-h treatment presented the greatest number of P/AI for younger cows (≤ 3 yr), but for older cows, inseminations anytime 56 h or later produced the most P/AI. Overall pregnancy rates at d 63 were greatest for the 56-h treatment, with the fewest pregnancy losses. Given the interactions that seem to exist among location, cycling status, and age, further work is necessary to better define these relationships with the applied protocol.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

The fluid flow channels of modern heat exchangers are often equipped with different flow disturbance elements which enhance the convective heat transfer coefficient in each channel. These structural or surface roughness elements induce enhanced flow mixing and convective heat transfer at low Reynolds numbers (500 < Re < 2200) by fluid mixing near the channel walls and increasing the surface area. These elements, however, are accompanied by higher pressure drops in comparison to hollow smooth channels (without inserts). The Run-Around Membrane Energy Exchanger (RAMEE) system is an air-to-air energy recovery system comprised of two remote liquid-to-air membrane energy exchangers (LAMEEs) coupled by a pumped liquid desiccant loop. LAMEEs use semi-permeable membranes that are permeable to water vapor, but impermeable to liquid water. The membranes separate the liquid desiccant from the air flow channels, while still allowing both heat and water vapor transfer. The air channels are equipped with turbulence enhancing inserts which serve dual purposes: (a) to support the adjacent flexible membranes, and (b) to enhance the convective heat and mass transfer. This research experimentally investigates the increase in the air pressure drop and average convective heat transfer coefficient after an air-side insert is installed in a Small-scale wind tunnel for exchanger insert testing (WEIT) facility that is designed to simulate the air channels of a LAMEE and to measure all the properties required to determine the flow friction factor and Nusselt number. Experiments are conducted in the test section under steady state conditions at Reynolds numbers between 900 and 2200 for a channel with and without inserts. The 500-mm-long test section has a rectangular cross section (5 mm wide and 152.4 mm high) and is designed to maintain a specified constant heat flux on each side wall. The flow is laminar and hydrodynamically fully developed at the entrance of the test section and, within the test section, thermal development occurs. Nine different insert panels are tested. Each insert is comprised of several plastic rib spacers, each aligned parallel to the stream-wise direction, and several cross-bars aligned normal to the flow direction. The plastic rib spacers are placed either 30 mm, 20 mm or 10 mm apart, and the distance between the cylindrical bars is either 30 mm, 45 mm, 60 mm or 90 mm. The measured convective heat transfer coefficient and the friction factor have uncertainties that are less than ±7% and ±11%, respectively. It is found that the Nusselt number and friction factor are dependent on the insert geometry and the Reynolds number. An empirical correlation is developed for the inserts to predict Nusselt number and friction factor within an air channel of a LAMEE. The correlations are able to determine the Nusselt number and the friction factor within ±9% and ±20% of the experimental data. Results show the flow insert bar spacing is the most important factor in determining the convective heat transfer improvement. As an application of the experimental data in this thesis, the experimental and the numerical results from a LAMEE which has an insert in each airflow channel are presented. The results show that the insert within the air channel of the LAMEE is able to improve the total effectiveness of the LAMEE by 4% to 15% depending on the insert geometry and air flow Reynolds number and operating inlet conditions for the exchanger.

The Diploma Thesis is focused on the implementation of FCAW welding technology to the manufacturing process of a mechanical engineering company. One part of implementation is partial automation of manufacturing process with positioner machine which is connected to the welding source. Practical part of Diploma Thesis includes the verification of the weldability of used materials and assigning of pWPS for subsequent qualification of the welding process WPQR with the welding technology FCAW.

Cette étude concerne un système de stockage d’énergie thermique par changement de phase, de type tubes et calandre et destiné à être raccordé à la sous-station d’un réseau de chaleur. Le travail s’axe autour des transferts thermiques dans le MCP et du régime de convection dans le fluide caloporteur.La première étude expérimentale s’attache à montrer l’importance des inserts à l’intérieur du tube où circule le fluide caloporteur, pour sortir des régimes de convection mixte défavorables au système. Deux tubes ailettés sont testés avec deux types d’insert différents. Les inserts testés sont cylindriques et hélicoïdaux. Les performances thermiques sont meilleures avec ces derniers. Les tubes ont des densités d’ailettes suffisamment élevées pour que les transferts thermiques par convection, dans le MCP, soient négligeables. Une approche analytique a permis d’estimer les conductivités thermiques effectives dans le MCP au contact des ailettes à partir des résultats expérimentaux. Elles sont estimées à 7,4 et 10,9 W/m/K pour des densités d’ailettes de 7 et 10 fpi respectivement.La seconde campagne expérimentale se penche sur des géométries d’échangeurs novatrices : des tubes équipés soit d’une mousse stochastique en cuivre, soit d’une mousse régulière en aluminium. Les conductivités thermiques effectives sont estimées à 13,4 et 39,5 W/m/K respectivement. Le potentiel de ces échangeurs est mis en avant à travers des comparaisons avec d’autres géométries d’échangeurs. En particulier, l’échangeur à mousse de cuivre permet de transférer plus d’énergie en un temps plus court qu’un échangeur à ailettes radiales en cuivre, bien que la quantité de cuivre dans la mousse soit moindre que dans les ailettes.Enfin, un modèle numérique de CFD 2D-axisymétrique est validé expérimentalement. Ce modèle confirme que la convection naturelle a une influence négligeable sur les performances thermiques à l’échelle du système, mais qu’elle joue un rôle dans la forme du front de fusion entre et en périphérie des ailettes. / This study is about a shell and tubes latent heat thermal energy storage system. This system is expected to be integrated in a district heating network substation. Heat transfers inside the PCM as well as convection flow regime inside the heat transfer fluid are investigated.A first experimental study aims at demonstrating the necessity of internal insert inside the tubes in order to avoid mixed convection flow regime. Two highly finned tubes as well as two inserts are tested. Inserts are either cylindrical or helical. Better thermal performances are obtained with the helical one. Besides, it is shown that free convection, between the fins is negligible. Effective thermal conductivities are estimated with an experimental and analytical approach at 7.4 and 10.9 W/m/K for the 7 fpi and the 10 fpi tube.A second test campaign is carried out with metallic foams. The first one is stochastic and in copper while the second one is regular and in alumina. Effective thermal conductivities are around 13.4 and 39.4 W/m/K respectively. The copper foam heat exchanger is shown to be better than a copper finned tube in terms of stored energy and thermal power, whereas only half the mass of the fins is used in the foam.Eventually a CFD numerical model is experimentally validated. This model shows that free convection inside the PCM is negligible on the overall thermal performances even though it modifies the solid/liquid interface shape locally.

iv Abstract The MA thesis examines the word-formation potential of expletive insertion with simple and complex words in English. It represents a linguistic phenomenon that is commonly used by native speakers, shows a certain degree of regularity and has gained popularity with the rise of the Internet, social media and the movie industry. The theoretical part introduces the previous studies on the phenomenon and presents the basic features of the phenomenon, namely the categorization of inserts and the classification of their positions in terms of the structure of the base as outlined by McMillan (1980). The extraction of the sample is described in the methodology section. The empirical part examines the phenomenon's main principles of use governed by prosody and morphology and illustrates the properties and both regularities and irregularities that the process exhibits (predictable insert position, poly-syllabicity of the base, its unchanged meaning and syntactic category, alternative categories of input bases and morphematic discontinuity of bases). The analysis comprises of two main parts: the study of the inserted bases (word-class, type of base, simple vs. complex, and a number of syllables) and the study of the expletive insert (representation of individual inserts and their position relative to stress...

Sandwichplatten sind effiziente Leichtbauelemente. Sie werden im Fahrzeugbau, in der Luft- und Raumfahrt, im Werkzeugmaschinenbau und überall dort, wo es auf geringe bewegte Massen ankommt, eingesetzt. Sandwichplatten sind oft Halbzeuge. Sandwichbauteile haben oft einen aufwendigen Herstellungsprozess, der eine Wärmebehandlung, die höhere Genauigkeiten ausschließt, beinhaltet. Aus diesen Gründen ist es oft sinnvoll, Inserts erst im Nachhinein in die fertige Sandwichplatte bzw. in das fertige Sandwichbauteil einzusetzen. Diese Inserts haben unterschiedliche Aufgaben. Sie dienen z.B. der Aufnahme von Schrauben, Bolzen und Lagern. Die vorgestellte Verbindung entspricht durch ihre spezielle Geometrie den hohen Anforderungen für Verbindungselemente in den genannten Gebieten hinsichtlich Genauigkeit und Stabilität. Es wird der Konstruktionsprozess eines Inserts für Sandwichplatten aus CFK- Verbundmaterial beschrieben. Ausgehend von einer patentierten Lösung der Autoren findet eine schrittweise Produktverbesserung bis hin zu einem einsatzfähigen Prototypen statt. Durch die Insertverbindung können für den Maschinenbau erforderliche Genauigkeiten nun mit CFK- Halbzeugen umgesetzt werden. Die Anwendung dieses Leichtbaupotentials führt zur Energieeinsparung und zum Transfer von CFK- Anwendungen in den Maschinenbau.

Ziel der vorliegenden Arbeit ist die Entwicklung eines neuartigen Ferti-gungsprozesses für hochfunktionalisierte Strukturbauteile in PFH-Technologie. Eigens für die Verarbeitung von FKV-Profilen wird das IHU/Spritzgießverfahren grundlegend analysiert und die einzelnen Pro-zessstufen durch den Einsatz geeigneter Prozessmedien und -parametrierungen modifiziert. Mit Hilfe umfangreicher analytischer und numerischer Berechnungen sowie erfolgreicher Umsetzung eines neuar-tigen Temperierungskonzeptes lassen sich erstmals FKV-Profile ohne den Einsatz von Barriereschichten, endkonturnah und reproduzierbar in seriellen Taktzeiten umformen. Zudem ist somit eine Funktionalisierung mittels Spritzgießen und ein gesamtheitliches Beherrschen des Hybrid-prozesses gegeben. Ein Vergleich der Verbindungsfestigkeiten mit hyb-riden Referenzbauteilen beweist, dass sich durch die stoffschlüssige Anbindung zeit- und kostenintensive Vorbehandlungen einsparen und gleichzeitig höhere Verbundqualitäten erzielen lassen. Um das PFH-Strukturbauteil mit montagegerechten Verbindungsschnittstellen zu werkstofflich andersgearteten Multimaterialstrukturen zu versehen, dient ein eigens entwickeltes prozesskomplementäres In-situ-Integrationsverfahren. Abschließend ist ein allgemeiner methodischer Ansatz für den technologischen Transfer und Adaption systematisch aufgeschlüsselt, sodass sich die einzelnen Entwicklungspfade nachvoll-ziehen lassen.:1 Einleitung 2 Zielsetzung 3 Stand der Wissenschaft und Technik 4 Anforderungen an einen faserverbund-gerechten IHU/Spritzgießprozess 5 Prozessentwicklung und Validierung 6 In-situ-Integrationsprozess für metallische Inserts 7 Konfiguration einer seriellen Fertigungstechnologie 8 Zusammenfassung und Ausblick Anhänge / The goal of this thesis is the development of a new production technol-ogy for highly functional lightweight structural parts. Therefor the hy-droforming supported overmolding process was chosen as a suiting manufacturing process. By usage of analytical and numerical calcula-tions as well as adapting a new kind of temperature distribution con-cept, the new Polymer-FRP-Hbyrid-Technology is enabled to manufac-ture frp-profile based structural components without the need for a barrier layer. The final product possesses its’s final shape already and has no need for further machining processes. A comparison with state-of-the-art metal-plastic-hybrid bonding systems shows a way higher value for the new technology due to the adhesive bond between the tape and injection molding polymer. Furthermore, the technology was enhanced with a process implemented insert joining process. Finally, a methodical approach for the technology transfer is presented.:1 Einleitung 2 Zielsetzung 3 Stand der Wissenschaft und Technik 4 Anforderungen an einen faserverbund-gerechten IHU/Spritzgießprozess 5 Prozessentwicklung und Validierung 6 In-situ-Integrationsprozess für metallische Inserts 7 Konfiguration einer seriellen Fertigungstechnologie 8 Zusammenfassung und Ausblick Anhänge