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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

An Integrated Methodology for Design of Distribution Chain

Ma, Hongze January 2004 (has links)
In today’s buyer market, the key question for an enterprise is how to sell products rather than how to produce products. That is why the study on distribution part of a supply chain is attracting extensive attentions from both academics and industry. In this dissertation, an integrated methodology is developed to design a istribution chain. According to this methodology, a distribution chain is designed by following three phases: (1) Problem formulation phase. In this phase, the present situation for the host enterprise is analyzed, and the goal to design this distribution chain is set. By this analysis, the objective and constraints for designing the distribution chain are determined. (2) System design phase. In this phase, first, all possible istributors are evaluated through a trilogy: -Determine the factors needed to be considered when evaluating a possible distributor. - Collect data from geographically distributed distributors by a mobile agent based information acquisition system. - Evaluate possible distributors quantitatively by a FL (Fuzzy logic)-ABL (Array Based Logic) inference engine. After evaluation, a set of eligible distributors are selected as andidates for designing this distribution chain. With these candidates at hand, a set of models, formulae and lgorithms are developed to design a distribution chain. To determine the exact customer demand at each retailer (candidate), an ANN Artificial Neural Network) model is developed to estimate the retailer’s market share in its customer zone. By this estimated market share, the customer demands at retailers are determined, and the configuration of a distribution chain, including the number and location of distributors, is determined by MIP (Mixed Integer Programming) model. The inventory control parameters at each node of this distribution chain are optimized by probability theory, and routes for vehicles to deliver products between different nodes are optimized by genetic algorithm. After this, the designing process for a distribution chain is finished. (3) Performance evaluation phase. To verify the design result, a new form of Petri net, combinatorial Petri net, is developed, and the performance of the distribution chain designed above is evaluated by this newly developed Petri net form. If the performance is not satisfactory, the distribution chain needs to be re-designed. All models, algorithms and formulae used in this dissertation have been implemented by computer applications. This gives possibility to realize automatic design of a distribution chain. At last, a umerical example is given to illustrate how to apply this methodology in practice.
52

Detection of Rifampicin Resistance in Mycobacterium tuberculosis by Padlock Probes and Magnetic Nanobead- Based Readout

Engström, Anna, Zardán Gómez de la Torre, Teresa, Strømme, Maria, Nilsson, Mats, Herthnek, David January 2013 (has links)
Control of the global epidemic tuberculosis is severely hampered by the emergence of drug-resistant Mycobacterium tuberculosis strains. Molecular methods offer a more rapid means of characterizing resistant strains than phenotypic drug susceptibility testing. We have developed a molecular method for detection of rifampicin-resistant M. tuberculosis based on padlock probes and magnetic nanobeads. Padlockprobes were designed to target the most common mutations associated with rifampicinresistance in M. tuberculosis, i.e. at codons 516, 526 and 531 in the gene rpoB. Fordetection of the wild type sequence at all three codons simultaneously, a padlock probe and two gap-fill oligonucleotides were used in a novel assay configuration, requiring three ligation events for circularization. The assay also includes a probe for identificationof the M. tuberculosis complex. Circularized probes were amplified by rolling circle amplification. Amplification products were coupled to oligonucleotide-conjugatedmagnetic nanobeads and detected by measuring the frequency-dependent magneticresponse of the beads using a portable AC susceptometer.
53

Investment Strategy Under Differential Technology Competition:Using the Real Options Approach

Ho, Chia-lung 25 July 2005 (has links)
Because of the high cost and the irreversibility of the big investment company decision maker often choose to defer the investment until the uncertainty gets clear. That is a management flexibility to decrease the risky. This article analyze that when company faces two competing technology that one have competing advantage comparing with the other under an uncertainty situation how does the company decide when and which to adopt. We develop a continuous-time stochastic model that aids in determination of optimal timing for adoption within the framework of real options theory. We propose that the competing situation between two incompatible technologies follows the general Wiener Process. When company chose to defer the investment we use the expectations of the decision maker and the competing situation between two technologies to decide the optimal investment timing. The result of this thesis suggests that a technology adopter should defer its investment until one technology¡¦s probability to win out in the market place and achieve critical mass reaches a critical threshold. This research only provides a way to show the decision maker when and which to adopt but not guarantee that the technology being chose will dominate the market in the future.
54

Theoretical investigation of water vapour condensation in presence of noncondensable gases

Karkoszka, Krzysztof January 2005 (has links)
<p>Steam condensation phenomenon plays an important role in many industrial applications. Especially in energy sector this process requires deep understanding. When noncondensable gases are taken into consideration description of the entire phenomenon becomes more complicated. If the surface condensation is taken into consideration this additional species accumulates and creates noncondensable layer near the surface on water vapour condenses. Due to this effect heat and mass transfer rates from gas mixture decreases. Also volume condensation (if it occurs) is affected by the presence of inert gases.</p><p>Several examples where the phenomena described above are important can be taken into consideration: studies of accidents in the nuclear power plants where condensation in the volume and condensation on the cold containment’s structures occurs after steam is released due to the pipe brake in the primary loop (especially this is important for PWR’s containments which in normal operation conditions are filled with air or nitrogen); condensation of steam in the pipe systems of BWR reactors where some amount of hydrogen can be accumulated due to the water vapour condensation in nonvented pipes; condensation of steam in the condensers after low pressure stage turbine; etc. Also in other fields, e.g. chemistry or meteorology, the condensation of water vapour in presence of noncondensable species plays very important role.</p><p>Diffusion surface condensation model and its implementation into CFX – 4 CFD code has been described in this licentiate thesis. Three different situations have been taken into account: surface condensation of water vapour in presence of air on the vertical wall (computational results have been compared with several commonly used correlations), surface condensation of water vapour in presence of air on the horizontal wall (results have been compared with experimental data), volume condensation in presence of air (known also as spontaneous condensation) – principle of the model has been described and calculation example has been presented and analysed.</p> / QC 20100623
55

Crystallisation of star polyesters with poly (ε-caprolactone) arms : approaching the problem of early stages in polymer crystallisation

Núñez, Eugenia January 2004 (has links)
<p>The knowledge regarding early stages in polymer crystallisation remains inconclusive due to experimental limitations. The reason is that the initially formed polymer crystals rearrange rapidly at the crystallisation temperature. Faster experimental techniques or simulation would be suitable alternatives to approach the problem. Another possibility would be to use constrained polymer structures, in which crystal rearrangement would be slower. Star polymers with crystallisable arms may be structures sufficiently constrained to be captured in their early crystallisation stages.</p><p>This study reports the crystallisation behaviour of linear poly(c-caprolactone) (PCL) and star polymers based on dendritic cores with grafted PCL arms. Wide angle X-ray scattering proved that the crystal structures of the different polymers were the same. The samples were also studied by differential scanning calorimetry, finding that the star PCL’s had lower crystallinity, lower rate of crystal rearrangement and higher equilibrium melting point than the linear analogues. Polarized optical microscopy showed that the star polymers crystallized slower and had greater tendency to form spherulites and higher fold surface free energy than linear PCL. The single crystal morphology was more irregular in the star polymers as observed by transmission electron microscopy.</p><p>These findings confirm the constraining effect of the dendritic cores in the crystallisation of the PCL arms, which retard molecular rearrangement during crystallisation and turn the studied star polymers into excellent candidates to investigate the early stages in polymer crystallisation.</p>
56

The pearl /

Stewart, Christine. January 1900 (has links)
Project (M.F.A.) - Simon Fraser University, 2004. / Theses (School for Contemporary Arts) / Simon Fraser University. Also issued in digital format and available on the World Wide Web.
57

The "STEPS" Camp interface CD

Brenholt, Michael A. January 2002 (has links) (PDF)
Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2002. / Field problem. CD version is available in the Stout Archives for in-house use.
58

Middle school principals' perception of the effect of technology on job effectiveness

Blackwell, James Michael. January 2009 (has links)
Thesis (Ed.D.)--Marshall University, 2009. / Title from document title page. Includes abstract. Document formatted into pages: contains viii,115 p. Includes bibliographical references p. 98-106.
59

Factors that prevent female students from enrolling in technology education courses at Richfield Senior High School

Waite, William G. January 2003 (has links) (PDF)
Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2003. / Includes bibliographical references.
60

The relationship of technology transfer and absorptive capacity an empirical study for Taiwan and China /

Wang, Eade. Unknown Date (has links)
Technology transfer (IT) is a concept embodied with many complex factors. This study focuses on Research and Development (R&D) Absorptive Capacity (AC) of both ends of the partnership during IT. / Thesis (DBA(DBusinessAdministration))--University of South Australia, 2005.

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