922 resultados para Parametric modeling of repair time
Resumo:
Time-dependent fluctuations in surface-enhanced Raman scattering (SERS) intensities were recorded from a roughened silver electrode immersed in diluted solutions of rhodamine 6G (R6G) and congo red (CR). These fluctuations were attributed to a small number of SERS-active molecules probing regions of extremely high electromagnetic field (hot spots) at the nanostructured surface. The time-dependent distribution of SERS intensities followed a tailed statistics at certain applied potentials, which has been linked to single-molecule dynamics. The shape of the distribution was reversibly tuned by the applied voltage. Mixtures of both dyes, R6G and CR, at low concentrations were also investigated. Since R6G is a cationic dye and CR is an anionic dye, the statistics of the SERS intensity distribution of either dye in a mixture were independently controlled by adjusting the applied potential. The potential-controlled distribution of SERS intensities was interpreted by considering the modulation of the surface coverage of the adsorbed dye by the interfacial electric field. This interpretation was supported by a two-dimensional Monte Carlo simulation that took into account the time evolution of the surface configuration of the adsorbed species and their probability to populate a hypothetical hot spot. The potential-controlled SERS dynamics reported here is a first step toward the spectroelectrochemical investigation of redox processes at the single-molecule level by SERS.
Resumo:
Setup time reduction facilitate the flexibility needed for just-in-time production. An integrated steel mill with meltshop, continuous caster and hot rolling mill is often operated as decoupled processes. Setup time reduction provides the flexibility needed to reduce buffering, shorten lead times and create an integrated process flow. The interdependency of setup times, process flexibility and integration were analysed through system dynamics simulation. The results showed significant reductions of energy consumption and tied capital. It was concluded that setup time reduction in the hot strip mill can aid process integration and hence improve production economy while reducing environmental impact.
Resumo:
Research question: How has the presence of PT employees affected the role of managers in the Swedish food retail business? Research purpose: The purpose of this paper was to describe the change that accompanies part-time employment from a management perspective, and particularly, describe how the presence of part-time employment has influenced the role of the manager within the Swedish food retail business. Conceptual framework: The main focused in this chapter is directed towards the role of managers. The basis of the conceptual framework consist of the model developed by Mintzberg including the ten managerial roles and Quinn's eight leadership roles and how the presence of PT employments might affect these roles. Methodology: In this paper, the authors adopted a qualitative design and used narrative inquiry as a research strategy in order to gain a deep understanding of the context. Semi- structured interviews have been collected through a self-selection sampling and the total number of participants was ten. Conclusions: Based on the findings of this paper the presence of PT employees have not influenced and changed the role of managers. The changes that have influenced and caused the change of the role of the managers constitutes of the increased workload, the delegations of tasks and responsibilities, changed positions, the change of the organisational structure of the individual store, and the increased workforce.
Resumo:
In this paper we investigate how attitudes to health and exercise in connection with cycling influence the estimation of values of travel time savings in different kinds of bicycle environments (mixed traffic, bicycle lane in the road way, bicycle path next to the road, and bicycle path not in connection with the road). The results, based on two Swedish stated choice studies, suggest that the values of travel time savings are lower when cycling in better conditions. Surprisingly, the respondents do not consider cycling on a path next to the road worse than cycling on a path not in connection to the road, indicating that they do not take traffic noise and air pollution into account in their decision to cycle. No difference can be found between cycling on a road way (mixed traffic) and cycling in a bicycle lane in the road way. The results also indicate that respondents that include health aspects in their choice to cycle have lower value of travel time savings for cycling than respondents that state that health aspects are of less importance, at least when cycling on a bicycle path. The appraisals of travel time savings regarding cycling also differ a lot depending on the respondents’ alternative travel mode. The individuals who stated that they will take the car if they do not cycle have a much higher valuation of travel time savings than the persons stating public transport as the main alternative to cycling.
Resumo:
Each section of this thesis will be subdivided into three parts encompassing all of the research in which I have been involved during the past three years. These will be referred to under the headings "Syntheses:' "Molecular Modeling," and "Cross-linking Efficiencies." Each of these subdivisions may have divisions within them when necessary in order to fully detail the research.
Resumo:
This thesis examines the story of how Goya came to be the artist he was and of the times which made him what he was, and which he so well mirrored. Francisco Goya y Lucientes is a remarkable figure in the history of art. Rarely has an artist arisen from such a cultural vacuum; rarely has an artist done so much to establish a cultural reputation for his country; rarely has an artist reflected so accurately the spirit of his time; and rare is the artist who has such an important influence on all the significant art of the future.