This thesis focuses on the new product development (NPD) process and the organizational structure which supports the process. The expected payoff method is borrowed from economic theory and is modified to be able to quantitatively evaluate processes. The method is used to evaluate and compare sequential and concurrent engineering processes. The method is also used to evaluate different organizational structures that support NPD processes. Thus, the relationship between process effectiveness and organizational structure is investigated. Study results are compared with observations of actual NPD processes and organizational structures. A third part of this thesis develops an analysis technique for the study of the dynamic task coupling which takes place in concurrent engineering. The ability to determine a dynamic ordering of tasks is compared to the static ordering given by the Design Structure Matrix method.

This thesis presents a new method for the prioritization of maintenance and repair (M&R) activities related to engineering facilities. Only M&R that can be programmed into a two to three years budgeting cycle are considered in the ranking procedure. Tasks that are of an emergency nature and that must be accomplished immediately are beyond the scope of this thesis. / The methodology is intended to assist in a rational allocation of M&R funds by generating a priority list of tasks based on component importances and conditions. The premise is that the most important component in the worst condition is given the highest priority. The methodology is then applied to embankment dams, where M&R activities are performed to prevent (1) the failure of the dam (prevention system) and (2) to maintain the ability to detect the presence or absence of undesirable condition (detection system). Both systems are treated separately, and two independent lists of prioritized activities result from the ranking procedure. The reliability of the monitoring system in detecting undesirable conditions is used to reassess the relative importance of the components of the prevention system. / Finally, the proposed methodology is applied to two embankment dams, the first one (TA-24) is operated by Hydro-Quebec, and the second one (Lewisville) by the U.S. Army Corps of Engineers.

The degree of waste paper recycling has been increasing steadily in North America over the last decade. Flotation is a popular method for removing ink from fibres (deinking) and is traditionally performed in mechanical cells. Column flotation has been proposed as an alternative to mechanical cells. In this work, open and packed laboratory and pilot-scale columns were operated to determine their relative merits and how they compare to a circuit of mechanical cells. / It was found that the type of sparger was critical for obtaining high flotation efficiencies. Fine porous stainless steel spargers (0.5 $ mu$m) produced flotation efficiencies which were equal to those of the mechanical cells. Packing was effective in increasing flotation efficiency when the coarse porous stainless steel sparger (100 $ mu$m) was used in the laboratory column and when the variable gap sparger was used in the pilot column. / The organic loss from all column configurations (laboratory and pilot-scale) was less than 3%. / The scale up procedure was evaluated using data from the laboratory column and pilot column dimensions. Finally, using data from the laboratory column, industrial columns were designed.

This numerical modeling study consists of two main parts. The first part is related to the simulation of industrial scale continuous slab casting systems, while the second part deals with the simulation of a twin-roll thin-strip casting process. In the first part, a numerical investigation was conducted for exploring the steady state transport phenomena of coupled turbulent flow, heat transfer and macroscopic solidification in a continuous stainless steel slab caster. The solidification of molten steel was modeled through the implementation of the popular enthalpy-porosity and/or continuum modeling techniques. A series of simulations was carried out to investigate the effects of the casting speed, the delivered superheat, the immersion depth of the twin-ported submerged entry nozzle (SEN) and mold wall heat extraction rate on the velocity and temperature distributions and on the extent of the solidified and mushy regions on the narrow and broad faces of the caster. / Next, the model was further developed to take into account two other important aspects of the continuous casting processes, namely electromagnetic flow control and bubble gas injection. For the electromagnetic part, the continuum model equations were solved simultaneously to study the usefulness of five different commercially used electromagnetic braking (EMBR) configurations in continuous slab casting processes. The predicted results showed that the minimum thickness of the solidifying shell at the mold exit increases due to the application of the EMBR devices. / In a separate effort, the program was further advanced by incorporating the multiphase continuum model for simulating the argon gas bubble injection via the submerged entry nozzle (SEN) into the mold. The predicted results from this study showed that the flow pattern and temperature distribution were significantly influenced by the bubble injection especially in the upper part of the mold. The gas bubbles with smaller sizes were found to travel deeper towards the narrow face of the slab and spread wider in the mold. / In the second part, a numerical study was carried out to investigate the two-dimensional turbulent flow, heat transfer and macroscopic solidification in a twin-roll thin-strip casting machine. The arbitrary nature of the computational domain was accounted for through the use of a non-orthogonal boundary-fitted coordinate (BFC) system on a staggered grid. The developed code was later used to study the sensitivity of the model parameters such as Darcy coefficient and turbulent viscosity modification factor in the mushy region as well as the effect of the casting parameters on the thin-strip twin-roll casting operations. (Abstract shortened by UMI.)

This thesis has focused on the measurement of gas holdup in flotation systems, a variable not measured reliably to date. / A sensor was designed using so-called flow conductivity cells. Their properties were studied and modelled, and their application in the design, construction, and operation of a gas holdup probe for use in flotation systems described. / A flow cell is defined as one that allows a fluid or dispersion to flow through freely while the electrical conductivity is measured. One of the most important features of a flow cell is the so-called cell constant. Once the cell constant is determined, the cell can be used to measure liquid and dispersion conductivity. The cell constant depends mainly on cell dimensions, and is largely independent of the characteristics of the fluid. / The addition of non conductive bodies to the fluid was studied. It was concluded that the cell constant is not affected by the presence of such bodies. These systems are described by Maxwell's model, which relates the fraction of non conductive phase (holdup) in the system to the conductivity of the continuous phase and the conductivity of the dispersion. / It was demonstrated that the electromagnetic field associated with the flow cells can be solved using the MagNet 5.1 software. Predicted results for cell constant were in good agreement with the experimental. The model holds the potential for design of flow cells for particular applications in mineral processing. / The gas holdup probe developed in this work applies the principle of separation of phases to fulfill the requirements of Maxwell's model. The probe consists of two flow cells. One, the open flow cell, measures the conductivity of the dispersion while the other, the syphon cell, measures the continuum conductivity. / The test work, in both laboratory and industrial flotation columns, demonstrated that the probe gave accurate estimates of gas holdup. The probe satisfied the requirements of an industrial sensor, as it performs in-situ, on-line, in real-time, with no external measurements and no assumptions regarding properties of any phase. / The gas holdup probe was used to explore operating flotation columns. It appears to hold great promise for diagnosis, readily detecting, for example, differences in gas holdup between sections of baffled columns. / This success may make the probe a candidate sensor for process control, although this will require a significant in-plant effort to realize. As a first step, the probe offers an opportunity to study the relationship between gas holdup and metallurgy, at least in flotation columns.

It has long been known that Soderberg aluminum smelters are a large source of anthropogenic polycyclic aromatic hydrocarbons in the environment. The atmospheric fate of polycyclic aromatic hydrocarbons is of importance to the aluminum industry in Canada due to their environmental persistence and potential health effects. For Soderberg smelters, the fate of facility emissions is of concern due to the involuntary nature of exposure by the general public in the surrounding regions. Excellent relationships between benzo[a]pyrene and polycyclic aromatic hydrocarbons between different types of Soderberg facilities and raw material formulations were found in the occupational environment during this investigation. This was followed by the comparison of emission profiles of a horizontal stud Soderberg aluminum smelter with profiles measured in a network of sampling stations in the adjacent community. The results suggested that benzo[a]pyrene may be less stable than the majority of the polycyclic aromatic hydrocarbons. An analysis of different sampling sites across Canada revealed that station profiles in the vicinity of Soderberg facilities were different from those found for sites impacted by steel plants, traffic and domestic heating. To explain some of the observed differences, it was hypothesized that polycyclic aromatic hydrocarbons on particulate matter approach a relatively stable profile that is based on the particle characteristics and source intensities. Particle size distribution measurements in the vicinity of the horizontal stud Soderberg aluminum smelter indicated that the majority of the polycyclic aromatic hydrocarbons were associated with particle aerodynamic diameter less than 3 mum. Furthermore, the cascade impactor measurements indicated that there was a sampling artifact of polycyclic aromatic hydrocarbons in-situ during sampling. Relationships for the levels of polycyclic aromatic hydrocarbons from 1997-2002 confirmed that ben

Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 112-131). Also available on the World Wide Web.

Thesis (Ph.D.)--Lehigh University, 2008. / Adviser: Theodore K. Ralphs.

Thesis (Ph.D.)--Lehigh University, 2008. / Adviser: Lawrence V. Snyder.

Thesis (Ph.D.)--Lehigh University, 2008. / Adviser: Lawrence V. Snyder.