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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.
231

The filtering of linear dynamic models with switching coefficients

Browne, Perry James January 1996 (has links)
No description available.
232

Restructuring Option Chain Data Sets Using Matlab

Baker, Alison M 29 April 2010 (has links)
Large data sets are required to store all of the information contained in option chains. The data set we work with includes all U.S. exchange traded put and call options. This data set is part of a larger data set commonly referred to as the National Best Bid Offer (NBBO) data set. The national bid best offer is a Securities and Exchange Commission (SEC) term for the best available ask price and bid price. Brokers must guarantee investors these prices on their trades. We have acquired data for the 5 year period from 2005 to 2009 for all U.S. traded options. Each year of data is approximately 6 gigabytes. The company, (DeltaNeutral - Options Data And End Of Day Downloads, 2010), from which we acquired the data, also has a software package, OptimalTrader, to process the data. For this data to be used in research projects, the data must be accessible by specific underlying security for selected date ranges. This type of data is more useful to the financial mathematics student than the output given by the software provided by DeltaNeutral. The software used in this data manipulation is Matlab. Each individual file of original data was parsed, and new files were written with some reformatting in which the original data was largely reorganized. The new organization will make searching for information from one stock or any specific group of stocks easier to achieve. We have created 3 m-files in Matlab which deal with reformatting the data, error handling, and searching through the original or reformatted data. The result is that new datasets can be created for further studying and manipulation. Future students working with this data should find this method, toolset, and the newly constructed datasets to be useful tools in working with options data and examining option chains.
233

Towards the absolute quantification of DNA by PCR

Burns, Nigel January 1999 (has links)
Amplification techniques such as the Polymerase Chain Reaction (PCR) are held to be largely qualitative procedures and are widely used as such. Since the efficiency of amplification is less than perfect, small changes in efficiency can yield dramatic differences in the final amount of product generated. Despite this unpredictability the exquisite sensitivity of PCR makes the demanding goal of absolute quantification highly desirable. Consequently, the use of this technique for the quantification of nucleic acids has increased at an exponential rate. However, the ability of PCR to accurately quantify absolute levels of DNA is still not universally accepted. The overall aim of this investigation was to determine the critical factors affecting the quantification of DNA using PCR and to use these findings to develop an assay for the absolute quantification of DNA in a model system. The novel work presented here illustrates the need for careful examination of sequencesfo r GC-rich domains which could give rise to stable secondary structures and reduce the efficiency of amplification by serving as termination sites. To determine the accuracy of competitive PCR, CE and IP-RP-HPLC were employed to quantify PCR- products. These two techniques provided valuable information on the identification and elimination of sources of error which led to improvements in speed, accuracy and precision, as well as ease of quantification by PCR. They also yielded information on the process of heteroduplex formation whilst simultaneously revealing assay limitations. Consequently, the on-line fluorescence monitoring of PCR was used as an alternative method for the quantification of Legionella pneumophila. This technique was highly reproducible however, mispriming and the subsequent amplification of non-specific PCR products limited the level of detection. The Y-end labelling of degraded DNA with DIG prevented short DNA fragments from mispriming (and consequently extending) allowing the amplification of DNA targets. Therefore, to reduce mispriming and hence improve assay sensitivity, this approach was adapted for the first time to produce 5'-degenerate, 3'- DIG-terminated competitive primer analogues. These analogues, coupled with the use of the LightcyclerTm, allowed the detection and absolute quantification of a single cell of Legionella pneumophila. This is the first time that this level of sensitivity has been achieved using this type of assay. This technique should provide a very rapid and sensitive alternative for quantification comparedt o the other,m oree xpensivete chnologiesa vailablea t present.
234

Molecular techniques for studing Fusarium ear blight of wheat

Doohan, Fiona Maria January 1997 (has links)
This work has compared polymerase chain reaction (PCR) assays and traditional visual disease assessment to evaluate the severity of Fusarium ear blight (FEB) ofwheat under field and glasshouse conditions. In a field trial, PCR analysis highlighted the problem of diagnosis of FEB of wheat based on visual disease assessment where natural inoculum was present. PCR-based analysis detected F. poae predominantly in the glumes and Microdochium nivale sub-species were predominantly found in the rachis component of ears. M nivale var. majus was more frequently observed than var. nivale (64 and 36 %, respectively). Quantitative PCR analysis and conventional visual disease assessment were used to evaluate fungicide efficacy against FEB of wheat caused by F. culmorum and F. poae in three glasshouse trials (1994/5-1996/7). Prochloraz and tebuconazole significantly decreased both visual symptoms of FEB and fungal DNA content of F. culmorum and F. poae ear blight of wheat. Overall, both fungicides appeared equally effective, although the efficacy ofthese fungicides was consistently greater as measured by PCR analysis rather than by visual disease assessment. Inoculation with F. culmorum significantly reduced yield (1000 grain weight) whereas inoculation with F. poae had no significant effect on yield. Fusarium culmorum was successfully transformed with the GUS reporter gene. GUS activity levels of transformants varied, but transformation did not affect pathogenicity on wheat seedlings. A GUS transformant was used to study the effectiveness of two fungicides against F. culmorum foot rot of wheat. Primers to the Tri5 gene were used to develop a PCR-based assay for the specific detection ofpotential trichothecene-producing Fusarium species. These primers were also used to develop an RT-PCR-based assay for the detection and semiquantification of F. culmorum Tri5 gene expression 'relative to p-tubulin gene expression' in RNA extracts from F. culmorum. This assay was used to show that time and fungicides can affect Tri5 gene expression in liquid culture.
235

The accountant's role in decision-making for retail discount chains

Zukoff, Martin January 1964 (has links)
Thesis (M.B.A.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-01
236

Supply chain visibility tools usage and their impact on on-time delivery : a case study of a fast moving consumer goods small, medium enterprise in London

Silvera, Yolanda January 2017 (has links)
The strategic importance of FMCG SME's supply chains makes it paramount that their performances are measured. Performance measurement in the context of on-time delivery is of high importance to SME's. SME's compete with large companies within the FMCG sector, as such gaining a competitive advantage is an extremely difficult task for these small and medium companies. There is an everincreasing interest toward the field of supply chain management and much attention has been deemed towards the importance of information sharing in gaining competitive advantage for SMEs. The integration of the chain both internally and externally through information sharing ( visibility) can lead to increase supply chain performance such as on-time delivery, therefore increasing competitive advantage for the SME's. The study aim to develop a conceptual framework and a model to evaluate the impact of visibility tools usage in FMCG SME's. This research highlights some visibility tools such as ERP systems, Sage software that influences the level of information shared among the parties within the SME supply chain. This research examined the potential of information technology based tools and visibility factors and aims to provide factors that may influence the sharing of information between suppliers and customers along the supply chain, thus meeting on time delivery schedules. This research employed both quantitative and qualitative approaches, with regression and correlation tests also conducted. Two questionnaires were administered, one at the case study company, the other at 100 SME's across London, 63 valid questionnaires were received and analyzed using SPSS software (manufactured by IBM, version 20). The findings of this research revealed that having shared values among SME's influenced the level of information that is shared and thus the level of visibility achieved within the supply chain. Further, it was revealed that large companies are able to utilize more in depth IT based systems, while small and medium sized companies had a tendency to utilize informal means for their visibility tools. In addition, the analysis of the research model indicated that supplier lead time and supplier chain reliability greatly influenced the ICT infrastructure of a FMCG SME. The model analysis also indicated that the delivery lead time influenced on-time delivery. In addition supply chain responsiveness was found to explain 30.9% of the variances found in supply chain visibility.
237

Utilização do fluxograma de processo para diagnóstico e integração da Cadeia logística " Supply Chain Management"

Ricardo Abreu de Oliveira, José January 2002 (has links)
Made available in DSpace on 2014-06-12T17:41:34Z (GMT). No. of bitstreams: 2 arquivo7318_1.pdf: 3907134 bytes, checksum: af97373928b4c23f70471b3cadc5592d (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2002 / O gerenciamento da cadeia logística e suprimentos "supply chain management" significa a integração completa de todos os parceiros e processos de uma cadeia logística. Este tem sido um objetivo perseguido por muitas empresas que buscam aumentar a competitividade diante de mercados cada vez mais concorridos. No entanto, como não há um padrão único a ser seguido, para integrar sua cadeia logística, uma empresa deve antes de tudo mudar a si mesma, passando de organização vertical para horizontal, fazendo com que todas as suas áreas e processos trabalhem de forma sincronizada, aqui surge a maior dificuldade enfrentada atualmente pelas empresas nesse processo. Diante desse quadro, este trabalho demonstra, através de simulação, como a utilização do fluxograma de processo pode contribuir para diagnosticar o estágio atual da cadeia, aperfeiçoar os fluxos de produtos e informações identificando as operações que não agregam valor, bem como as mudanças necessárias para reestruturação das atividades. Dessa forma, evidencia-se como através da análise de micro-processos a empresa pode estabelecer ações para otimizar o caminho crítico, gerar valor na cadeia logística, reduzir custos e aumentar a satisfação dos seus clientes
238

Environmentally conscious supply chain design / Strategische Planung von Wertschöpfungsnetzwerken unter Beachtung von Umweltaspekten

Altmann, Michael January 2014 (has links) (PDF)
Sustainability has become a critical topic in all areas of supply chain management. As discussed earlier, drivers for this development can be identified as both internal and external phenomena. Since customers are one of the key stakeholders in supply chain management, special attention is paid to the impact of costumers´ behavior on sustainable supply chain design decisions. In this context, two main research questions were analyzed: 1.What is the appropriate way to design a supply chain according to environmentally-oriented requirements of customers? 2.What is the impact of customer´s behavior regarding both usage and return of products on supply chain design decisions in an environmentally conscious closed-loop supply chain environment? Therefore, three different optimization models with various main aspects are developed. To illustrate how the presented models can be applied in practical problem cases, guidelines for implementing an environmentally supply chain design project are presented. / Das Thema Nachhaltigkeit stellt für eine Vielzahl von Unternehmen eine der Kernherausforderungen in der heutigen Zeit dar. Aufgrund der ökonomischen, ökologischen und sozialen Dimensionen, die in diesem Kontext zu beachten sind, nimmt die Komplexität von Unternehmensentscheidungen dramatisch zu. Besonders im Kontext des Supply Chain Managements, das nicht nur die unternehmensinternen Wertschöpfungsaktivitäten, sondern alle Prozesse der Produktentstehung über mehrere Akteure hinweg berücksichtigt, führt dies zu einer Zunahme an Parametern, die in die Planung einbezogen werden müssen. Neben anderen Treibern stellen Kundenanforderungen eine wesentliche Motivation zur nachhaltigkeitsorientierten Ausgestaltung von Supply Chains dar. Im Rahmen dieser Arbeit liegt der Fokus auf der strategischen Planung von Wertschöpfungsnetzwerken. Um die Wirkungszusammenhänge zwischen den zugrundeliegenden Planungsentscheidungen sowie möglichst alle relevanten Planungsparameter zu berücksichtigen, eignen sich mathematische Modelle zur Unterstützung von Entscheidungsträgern. Auf Basis von Literaturanalysen lassen sich jedoch nur wenige quantitative Ansätze in der Literatur identifizieren, die sich mit dem nachhaltigkeitsorientierten Supply Chain Design beschäftigen. Zudem kann eine Forschungslücke in der Berücksichtigung von Kundenanforderungen bei der strategischen Planung von nachhaltigkeitsorientierten Supply Chains festgestellt werden. Durch die Bearbeitung der folgenden Forschungsfragen, trägt die vorliegende Arbeit zur Schließung dieser Lücken bei: Wie können ökologieorientierte Kundenanforderungen bei der strategischen Planung von Wertschöpfungsnetzwerken berücksichtigt werden? Wie beeinflusst das Kundenverhalten in Bezug auf die Nutzung und die Rückgabe von Produkten Supply Chain Design-Entscheidungen im Kontext eines ökologieorientierten closed-loop Wertschöpfungsnetzwerks? Zur Analyse der Forschungsfragen werden drei mathematische Supply Chain Design-Modelle entwickelt. Zudem werden Empfehlungen zur Anwendung von nachhaltigkeitsorientierten Supply Chain Design-Modellen in Praxisprojekte präsentiert.
239

The Relation Between Preference and Demand in the Domestic Hen: Does Preference Vary With Price?

Bruce, Julie-Anne Marie January 2007 (has links)
ABSTRACT Six hens responded under an increasing Fixed Ratio schedule of reinforcement to assess demand separately for two different food types: wheat and puffed wheat. Demand curves generated showed the least preferred food, puffed wheat, yielded a higher initial (ln L) demand than the more preferred food, wheat. While responding for the more preferred food, wheat, produced lower initial (ln L) demand functions, responding for wheat was maintained to higher increasing FR schedules of reinforcement than was that for puffed wheat. This phenomenon occurred across all six hens. To assess preference between the two food types the hens responded under a two-link concurrent-chain schedule of reinforcement. Under the concurrent-chain schedule of reinforcement there were three conditions, each consisted of a initial link with VI 90-s VI 90-s in effect, and terminal links of FR1, FR8 and FR32. The concurrent-chain schedule was used to examine if or how preference may relate to demand. Preference measures obtained showed wheat was generally preferred to puffed wheat across all prices throughout the preference assessment. As price increased in the terminal link during the preference assessment, preference for wheat became more extreme as did the hens responding. The results suggest that while there is a systematic relation between preference and demand, in that at higher FR values food with higher demand levels is preferred. This does not seem to hold, however, at FR1
240

E-HEALTH – THE USAGE OF ICT DEVELOPING HEALTH CARE SYSTEM : MULTIPLE-CASE STUDY OF EUROPEAN COUTRIES DENMARK AND LITHUANIA

Kurtinaityte, Laura January 2007 (has links)
<p>Electronic health – this is the object of study work. The focus of research is European countries, which use Information and Communication Technologies improving their Health care system and it is not excepted is the country advanced in developing e-Health or it just started to create or improve this system. As it is a new Developing research area, there are not so many direct relevant researches about it previously found. Therefore it encourages the investigation of this topic, which according to European Commission and Enterprise Directorate General (2003) could reach greatest economy on saving costs in whole service sector. Thus the guidelines for efficient e-Health development should be given as soon as possible. The study work is exactly aimed on this.</p>

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