Thesis--Technische Universität Dresden, 2007. / Includes bibliographical references.

This thesis examines the effects of spatial location, Reynolds number and near exit flow modification on the development region of a round, free, turbulent jet. It is based on the publications generated by the author. The experiments were carried out over the range of Reynolds numbers between 10000 < ReD < 50000, where ReD is calculated based on the jet exit mean velocity and the nozzle exit diameter. The measurements were performed in the near- to intermediate-field region of a free jet defined between 0 ≤ x/D ≤ 30. In order to control the flow near the exit, two wire rings, with square cross-sections, of sides h = 1.5 mm, and outer diameter Dwire = 71.6 mm (positioned in the shear layer and called Rsl) and Dwire = 60 mm (positioned in the potential core and called Rpc) were placed at a stand-off distance downstream of the jet nozzle exit plane x/D = 0.03. Both stationary and flying hot wires were used to investigate the jet flow field. The results showed a considerable reduction in the jet spread rate and turbulence intensity using the passive rings. The reduction in the velocity decay rate was more obvious in the case of Rsl in lower Re; however, it was observed that as Re increases, the velocity decay rate became nearly the same for both cases of Rsl and Rpc. The axial velocity spectra showed the initial shear layer instability (shear layer mode) was suppressed while the jet preferred instability (preferred mode) remained active as the shear layer and potential core were modified. This shows the separation of these modes and is at variance with ideas that appeared in the literature that claimed the dependency of these two modes. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2012-04-27 16:06:31.03

Weftless Bead design has long been in existence and still used in many passenger car, bus, truck and agriculture tractors. The ideal bead design is a high strength flexible cable with minimal cross section and covered by rubberized nylon, rayon or steel wire side wall. The basic tire bead designs are weftless bead with rubberized ribbon of parallel wires of multiple wound layers and a continuous wire wound in sufficient number of loops to give the required strength. Weftless bead failures generally occur within about 5cm from the end of the overlapping parallel wire ribbon. The cause for this failure is generally attributed to the mounting process in which the diameter of the tire bead is changed during the mounting process in the well of the rim. A finite element model of the tire bead was developed and under the known stresses of the mounting and final use conditions. The Weftless bead generally consists of five steel wires in parallel in a continuous rubber tape or ribbons, which loosely secures the wires in a soft insulating rubber. The ribbon is wound into a hoop with four courses resulting in a grommet composed of a stack of wires. This ribbon with ten cut ends forming a splice, with five at the inner cut edge and five at the outer cut edge. A continuous bead formed from a single wire does not have this failure prone splice region. Field data and the finite element calculations show the failure point of the weftless bead is almost always at the under lap or at the starting point of the weftless bead. Continuous wire bead have significant advantages in safety over the Weftless bead still used in tires.

Titel: Säkerheten Främst – en kvalitativ studie av Sandviks interna säkerhetskampanj Nivå: C-uppsats i medie- och kommunikationsvetenskap, 15 högskolepoäng Författare: Caroline Holmström Handledare: Mats Hyvönen Examinator: Mathias Sylwan   Syfte: Syftet med uppsatsen är att studera hur de anställda på produktionsenheterna Wire Sandviken (WS) och Primary (PP) som ingår i produktområdet Wire and Heating Technology (WHT) inom affärsområdet Sandvik Materials Technology (SMT) på Sandvik har tagit emot kampanjen Säkerheten Främst samt att undersöka huruvida operatörer och flödeschefer har förslag på hur kommunikationsavdelningen vidare kan stötta säkerhetsarbetet och utveckla kampanjen. Dessa resultat diskuteras i förhållande till resultatet från en enkätundersökning vilken genomfördes 2014 vid WHT.                                                 Frågeställningar:     - Hur har kampanjen Säkerheten Främst tagits emot av anställda vid produktion på WS och PP? - Hur kan kampanjen Säkerheten Främst ytterligare utvecklas?   Metod: Kvalitativa, semistrukturerade intervjuer med flödeschefer och operatörer vid WS och PP. Totalt åtta respondenter vid fyra olika avdelningar.   Material och slutsats: Intervjuerna visade att även om respondenterna överlag var positiva till kampanjutformningen och budskapet, så var det inte alla som kommit i kontakt med kampanjen alternativt kommit i kontakt med alla kampanjelement. Förbättrad kommunikationsstyrning ses som nyckeln till att ytterligare utveckla kampanjen.   Nyckelord: Organisationskommunikation, intern kommunikation, Sandvik, Wire and Heating Technology, arbetsplatssäkerhet, kommunikationskampanj

7th IFAC Symposium on Advances in Automotive Control, The International Federation of Automatic Control, September 4-7, 2013. Tokyo, Japan

The goal of this thesis is to improve the understanding of the stitch bonding process in microelectronic wire bonding. In particular, it focuses on investigating the effect of the process parameters bonding force, scrub amplitude, and skid on experimental bond quality responses, including qualitative (non-sticking, sticking, and tail-lifting) and quantitative (stitch pull force, tail pull force). In addition to the experimental work, a finite element (FE) model is developed for the stitch bonding process using ABAQUS software, and compared with the experimental observations. For the first set of experiments, the stitch bonding is performed with a 18 ??m diameter Pd coated Cu (PCC) wire on a ???low bondability??? Au/Ni/Pd plated quad-flat non-lead (QFN) substrate. Results showed that a high bonding force, a high scrub amplitude, and a positive skid provoke the sticking of the stitch bond and reducing the chance of non-sticking observation. However, such parameters also increase the chance of tail-lifting. As a trade-off for a low bondability substrate, a process parameter combination containing a high bonding force and a high scrub amplitude and a negative skid could ensure a strong enough stitch bonding process with low chance of tail-lifting. For the second set of experiments, the stitch bonding is performed with a 18 ??m diameter uncoated Cu wire on a ???high bondability??? Ag plated QFN substrate. Statistical analysis of stitch and tail pull force showed that the skid and scrub parameters have a more significant influence than bonding force. A positive skid can degrade the stitch pull force, while enhancing the tail pull force. A high scrub amplitude is found to degrade both the stitch and the tail pull forces. The bonding force is shown to improve the stitch and tail pull forces slightly. Performing an optimization, process parameters of 70 gf (687 mN) bonding force, 3 ??m scrub amplitude, and zero skid result in acceptable stitch and tail pull forces, along with a reliable stitch bond appearance (low peeling and shallow capillary tool impression). The influence of the process parameters is significantly different depending on if bonding on low or high bondability substrates. For example, a positive skid increases the chances of sticking and tail-lifting on low bondability substrate, but it decreases the tail pull force and increases the tail pull force for high bondability substrate. This indicates that finding a general experimental rule for understanding the effect of process parameters on the stitch bond quality is difficult if not impossible. In other words, instead of general rule, it is more likely to find individual rules for specific individual applications. To improve the understanding of stitch bonding a three dimensional (3D) dynamic explicit FE model is developed in ABAQUS. The model components and boundary conditions are constructed and applied to reflect the experimental conditions. The bonding force, scrub, and skid are successfully implemented into the model. Mass scaling is applied carefully to save calculation time while ensuring there are no artificial effects of inertia. The model is able to render the conventional responses reported in the past including stress and strain distributions. However, these conventional outputs were not sufficient to provide a correlation between model and experiment. Therefore, new candidate responses were developed and extracted from the numerical results. The new responses are based on accepted welding mechanisms. One of the mechanisms is interfacial cleaning by frictional energy which is beneficial for bonding. Thus the friction energy accumulated during the simulated bond duration is extracted as a candidate response. For classical cold welding processes, the interfacial surface expansion is a key mechanism, as it opens up cracks in the surface contamination and oxide layers and thereby generates paths to bring the fresh metals together under pressure. Therefore, candidate responses related to surface expansion at the contact interface are extracted from the model. The complete set of new responses extracted from the numerical model includes contact areas, surface expansion per areas, frictional energy, and combination of frictional energy combined with surface expansions per areas. In addition the bond interface is divided into ???wedge??? and ???tail??? regions. The model is run for the same DOE cells as used in the first set of experiments and candidate responses are extracted and compared with the experimental observations. By ranking the correlation coefficients of each individual candidate responses, for the first time correlations that are relatively strong are found between a numerical response and experimental observations of stitch bonding. Responses that have correlation coefficients of 0.79 and 0.85 were found for wedge sticking and tail-lifting, respectively. Such relatively strong correlation indicates that the friction enhanced cleaning and the surface expansion mechanisms are proper theories for the current stitch bonding system. These theories can be used for developing similar models for other types of the solid-state bonding processes. Based on the best candidate responses, a procedure to determine numerical process windows is demonstrated for a specific application. Such a window defines the parameter ranges which result in an acceptable stitch bonding process and is an excellent indication of how suitable a process is for mass production. Depending on the application, materials, geometries, and tools, the FE model and process window procedure allow a variety of numerical process windows to be produced and compared.

HBO's The Wire examines the relationship between institutions and individuals in American society and concludes that institutions restrict the agency of individuals, and series creator David Simon likens the power of institutions to the gods of Greek tragedy. In this project, I argue that shame culture enables institutions to have the social influence described by Simon. The paper's introduction defines the term "shame culture" and distinguishes it from "guilt culture," and I use medieval examples of shame culture to illustrate how shame functions in The Wire. This paper divides its detailed discussion of The Wire into four sections, each of which focuses on a different institution. The essay's first section explores how drug dealers and criminals use their reputations aggressively to build drug empires or simply survive, as the characters Marlo Stanfield, a drug kingpin, and Omar Little, a stickup artist, demonstrate. The second section examines Marlo and Omar's influence on young drug dealers, called corner kids in the series, and I argue that the public schools cannot prevent shame from being ingrained in these children. The third section focuses on police officers and, specifically, eventual police commissioner Cedric Daniels, and I examine how the police department's preoccupation with crime statistics reveals their dependence on shame and reputation—the police force is ineffective since they mirror in many ways the criminals they are trying to arrest. Lastly, the essay's fourth section analyzes politicians in The Wire and how Mayor Carcetti is powerless to respond to and exacerbates the city's social problems due to his need to preserve his public image. The paper concludes that social reform that grants agency to individuals in The Wire is impossible as long as shame culture shapes the various institutions depicted in the series.

This thesis is concerned with the performance and measurement uncertainty of wire-mesh sensors in different air-water flow regimes in horizontal pipes. It also presents measurements of void fraction and interfacial velocity in such flows. It was found that the interfacial velocity measurements of the wire-mesh sensors were in good agreement with those taken with a high-speed camera and estimates of the uncertainties of these measurements are presented. Drift-flux models were fitted to the measurements and it was found that the parameters of these models were not only sensitive to the flow regime, but also to the liquid superficial velocity.

Thesis (M.S.)--University of Michigan, 1981.

Thesis (M.S.)--University of Michigan, 1963.