Dissertations / Theses: 'Generic firm'

1

Hickman, Richard James. "Generic integrated framework for improving inter-firm relationships : executive summary." Thesis, University of Warwick, 2009. http://wrap.warwick.ac.uk/38550/.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Candy, Ryan David. "Resources, Strategy and Performancein the Smaller Firm." Thesis, University of Canterbury. Management, 2009. http://hdl.handle.net/10092/3522.

Full text

Abstract:

This study investigates the relationship between firm resources, positioning strategies and performance in the smaller firm. Porter’s generic strategies have been useful in describing how firms compete in the marketplace, and the resource based view has shown that resources can lead to a sustained competitive advantage. The strategic management field has begun to combine the two theories and examine the link between them. Small firms must make the best use of their relatively scarce resources. It is proposed that the relationship between resources and performance is contingent upon the positioning strategy the firm competes on, although there has only been limited supporting research to date. This research builds on work by Edelman et al. (2005) by examining the relationship between human, organisational and physical resources, and the strategies of quality/ customer service, innovation, and cost leadership in 447 retail, engineering, and professional service firms in New Zealand. Using Structural Equations Modelling this research finds that positioning strategies are the mechanism by which firms can leverage their resources into higher performance. This relationship can be modelled as mediated or moderated, with statistical analysis sensitive to model complexity. The firm’s environment influences this relationship with different resources required to support each position depending on the industry. Specifically human, organisational, and physical resources appear to be viable sources of competitive advantage when they are leveraged by a strategy of quality/ customer service, innovation or cost leadership when the industry environment is conducive to the resource – strategy combination.

APA, Harvard, Vancouver, ISO, and other styles

3

Trieloff, Werner Dieter. "The competitive environment and generic strategy of a family run auditing firm in Brazil : a case study / Werner Trieloff." Thesis, North-West University, 2010. http://hdl.handle.net/10394/4592.

Full text

Abstract:

With the global financial crisis coming to a long awaited, though slow, end and the Fifa Soccer World Cup in 2014 and the Summer Olympic Games in 2016 having been awarded to Brazil in 2009, 2010 holds many challenges and an ever–diversifying environment in which a Brazilian firm needs to formulate and implement a competitive strategy. Over the last couple of years, Brazil has been a focus point for investors seeking high growth; however, the complex business environment has been a thorn in many international and national firms' side. With this complex environment as the starting point and many new opportunities as the future focus, Brazilian firms need to find accurate and relevant information about their environment, the markets, their competitors and their clients in order to choose the best strategy for the achievement of the overall goal of any company - increasing the wealth of the shareholder. The overall objective of this study is thus to use corporate planning tools to evaluate the internal and external environment of BAF Ltda in order to ensure that the best strategy is chosen and adopted so as to make the most of the opportunities that the coming years will bring. The planning tools utilised in this study are the SWOT and PEST analysis. Both have formed part of the strategic planning process of many firms over the past century and have proved to be a key part in putting together the information needed from which to build a sustainable strategy. This study evaluates both of these planning tools and applies them to the chosen company for this case study. Following on the corporate appraisal of the PEST and SWOT techniques, generic strategies are evaluated and suggested based on the information gathered through the analyses.
Thesis (M.Com. (Management Accountancy))--North-West University, Potchefstroom Campus, 2011.

APA, Harvard, Vancouver, ISO, and other styles

4

Sum, Vichet. "THE IMPACT OF TRAINING AND ITS INTEGRATION IN THE FIRM'S BUSINESS STRATEGIES ON THE FIRM'S COMPETITIVENESS." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1967978701&sid=6&Fmt=2&clientId=1509&RQT=309&VName=PQD.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Chen, Cheng. "Essays on Firm Organization and International Trade." Thesis, Princeton University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3642068.

Full text

Abstract:

This dissertation consists of three essays at the intersection of organizational economics and international trade. In the first essay, I investigate how the quality of management technology (MT) to monitor and incentivize employees affects aggregate economic outcomes. The key economic insight is that a common improvement in MT across all firms favors big firms, since these firms use management more intensively by adopting management hierarchies with more layers. This heterogeneous impact on firms with different numbers of layers creates a selection effect that the smallest firms exit the market, and the biggest firms expand. As a result, average firm size and aggregate productivity increase. In the second essay, I extend the baseline model developed in the first essay into the international context and investigate how an improvement in MT interacts with trade liberalization. Two theoretical results deserve particular attention. First, countries with better MT trade more with each other conditional on other factors. Second, a better MT amplifies the welfare gains from trade under certain conditions. Quantitative exercises show that an improvement in MT has quantitatively significant impacts on average firm size, aggregate productivity, and the welfare gains from trade. The final essay develops a general equilibrium model featuring an agency problem inside the firm (i.e., the separation of ownership and control) and points out a new channel through which trade liberalization leads to within-firm productivity gains. In the closed economy, managers working in the least productive firms exert effort higher than the second-best level to induce their owners to produce. After trade liberalization, a fraction of these managers is incentivized to exert more effort, since they still want to induce their owners to produce and continue to receive rents. Therefore, the least productive surviving firms whose ownership is separate from control receive productivity gains after trade liberalization.

APA, Harvard, Vancouver, ISO, and other styles

6

Kolasa, Artur. "Essays on Firm Behavior in Developing Countries." Thesis, The George Washington University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3610420.

Full text

Abstract:

This dissertation studies firm behavior and adaptation of firms in developing countries using firm-level data. Chapter 2 analyses the impact of business group membership on a firm's economic performance when operating in a suboptimal legal environment. The specific null hypothesis is that Indian firms in business groups have advantages in contract intensive industries, especially in Indian states with poorly functioning legal institution. A 2002 national judicial reform is used as quasi-natural experiment as an identification strategy. Chapter 3 further explores Indian business groups by looking at how ownership structure affects TFP, including the impact of family or corporate ownership. These two chapters suggest that business groups can have important economic affects at the firm level. Chapter 4 uses a World Bank firm level survey in 57 developing countries to examine whether MNC presence affects various measures of innovative output. We find that industrial, labor, and input proximities have a positive and significant impact on the likelihood of innovation when interacted with FDI concentration.

APA, Harvard, Vancouver, ISO, and other styles

7

Pantea, Smaranda. "International technology transfer, firm productivity and employment." Thesis, University of Nottingham, 2012. http://eprints.nottingham.ac.uk/13968/.

Full text

Abstract:

This dissertation contributes to the empirical literature on the effects of international technology transfer on firms' productivity and employment in developing and transition countries. It combines three empirical essays which provide evidence on how participation in international activities affects firms' productivity, how it interacts with firms' absorptive capacity and how it affects firms' demand for skilled labour in 26 transition countries in Europe and Central Asia (ECA) region. The first study investigates whether foreign ownership, supplying multinationals (MNEs) located in the same country, foreign direct investment (FDI) horizontal spillovers, exporting and importing are conduits of international technology transfer and their relative importance for firms in 26 transition economies in ECA region using Business Enterprise and Environment Performance Survey (BEEPS) 2002- 2005. It contributes to the literature by analyzing the impact of all main channels of international technology transfer simultaneously and by using a firm specific measure for supply linkages with MNEs, unlike previous studies that used industry level measures. The main results suggest that foreign ownership, supplying MNEs, exporting and importing are robustly associated with higher firm productivity and we cannot reject the hypothesis that these channels are equally important. The second study examines whether international technology transfer through foreign ownership, supplying MNEs, exporting and importing depends on firm and country absorptive capacity in 26 transition economies in ECA region using the BEEPS 2002 and 2005 waves. The main contributions of this paper are that it uses firm specific measures of access to foreign technology and measures of absorptive capacity (workforce education, personnel training and R&D activities) which are closely related to the concept of absorptive capacity and less prone to measurement errors than productivity gap measures used in previous studies. Our results suggest that access to foreign technology and absorptive capacity are associated with higher productivity, but, contrary to our hypothesis, there is no evidence of an interaction effect between absorptive capacity and access to foreign technology. The third study investigates how participation in international activities affects firms' demand for skilled labour and the ways in which firms respond to changes in demand for skilled labour in 26 transition economies in ECA during the period 2002-2005 using BEEPS 2002 and 2005 waves. It contributes to the literature by studying different ways in which firms respond to changes in the demand for skilled labour (hiring employees from outside the firm or training existing employees) and by studying whether there is a causal relationship between participation in international activities and demand for skilled labour. Our results suggest that firms engaged in international activities have a better educated labour force and are more likely to train their employees than domestic firms. However, this happens because firms with better skilled workforces and with formal training programmes select into participating in international activities, and not because these firms upgrade the skills of their workforces after starting to participate in international activities.

APA, Harvard, Vancouver, ISO, and other styles

8

Wood, Sarah. "Lost film found film." Thesis, University of Kent, 2015. https://kar.kent.ac.uk/48012/.

Full text

Abstract:

In an age where the historical event is mediated increasingly through the still and moving image, new stress is placed on the archival image as surviving evidence of and performer of history. Lost Film Found Film asks what the scope is for re-intervention by artists who engage with the documentary archival. What is found in their reappropriation? What is lost in the remix? Through a discussion of key works by Jean-Luc Godard, Hito Steyerl, Harun Farocki, Jayce Salloum, Johan Grimonprez and Eyal Sivan, Lost Film Found Film offers a definition and a description of what I have called the Cinema of Aftermath. I define this as cinema that evolved in the aftermath of the Second World War, that deploys found footage film not only as a form of critique but also as a form of participation in wider historical and political events. I argue that the Cinema of Aftermath comments on politics and is also political. Central to its project is a questioning of the potency of the archival image in both its self-reflexive and wider cultural use. In three chapters, I explore how the Cinema of Aftermath recalibrates the meaning and renews the formal possibilities of the documentary, and analyse the performance of memory, truth and evidence by this aestheticisation of archival image.

APA, Harvard, Vancouver, ISO, and other styles

9

Vella, Kevin James. "Selection by consequences and the marketing firm." Thesis, Cardiff University, 2015. http://orca.cf.ac.uk/74441/.

Full text

Abstract:

The research operationalizes the Darwinian meta-principle Selection by Consequences to conduct an empirical investigation. The project originates from a concern to understand the distal reasons why many of the marketing practices adopted by Wall’s appear to have persisted relatively unchanged for several decades and to have consistently conferred advantage to allow this manufacturer to dominate the UK ice cream market since before WWII. Central to Selection by Consequences is the claim that socio-cultural practices evolve through a process similar to biological natural selection and analogous to operant conditioning. The aim of the research is to assess and evaluate the empirical validity of this latter claim. A review of the literature suggests three pressing obstacles immediately barring the project, namely, relative incompleteness of the natural selection-operant conditioning analogy, methodological issues when applying operant principles (uncovered scientifically within experimental laboratories) to frame corporate market practices in the real world, and, insufficiency of these principles to account for the idiosyncrasies of the economic behaviour of organisations. The Marketing Firm provides the theoretical underpinning of this research because it begins to tackle the latter problems. After addressing these issues, the research interprets qualitative evidence narrating a 1979 investigation into the strategic practices of Wall’s conducted by the Monopolies and Mergers Commission. The inquiry is designed as a qualitative longitudinal case study. Generally, the evidence upholds the operant conditioning characterisation. However, several theoretical elaborations and empirically grounded refinements must be taken into account. Future research is directed towards further clarification and testing the analogy to destruction. As its primary original contribution, the research generates the first empirical study wherein Selection by Consequences is operationalized to produce an operant account of the evolutionary selection of marketing practices. The study also contributes by suggesting means to demonstrate, albeit qualitatively, processes typically identified through experimental methods and quantitative data.

APA, Harvard, Vancouver, ISO, and other styles

10

Jiang, Liwen. "Somatic embryogenesis and genetic transformation in douglas-fir." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/29882.

Full text

Abstract:

Cell division was obtained from cultured microspores of Douglas-fir on medium supplemented with auxin, cytokinin, and sucrose, but without medium salts. Embryogenic callus was initiated from excised mature and immature zygotic embryos of Douglas-fir on media supplemented with cytokinin and auxin. Precotyledonary embryos produced most of the embryogenic calli in the cultures. Secondary embryogenic callus production, and subsequent subculturing, were required for the establishment of stable embryogenic callus lines for both mature and immature zygotic embryos. Somatic embryos at the precotyledonary stage were obtained in high frequency when Douglas-fir embryogenic callus was transferred onto hormone-free medium supplemented with 1% activated charcoal, while some cotyledonary somatic embryos were obtained from hormone-free medium supplemented with low ABA levels (0-10 uM). The level of ABA in the maturation medium significantly affected the quality of the somatic embryos produced. Cell suspensions were established from embryogenic calli and have been maintained for over one year. Protoplasts were isolated from suspension, cell colonies and calli were regenerated from protoplasts. GUS and CAT genes were successfully introduced into protoplasts of Douglas-fir via electroporation, and their transient expression was obtained 2-4 days after electroporation. The results so far indicate that the production of somatic embryos via embryogenesis in vitro is obtainable, and the application of direct gene transfer via electroporation for genetic engineering of trees in this species is promising.
Forestry, Faculty of
Graduate

APA, Harvard, Vancouver, ISO, and other styles

11

Kadlecová, Lenka. "Optimální portfolio generické farmaceutické firmy maximalizující obrat." Master's thesis, Vysoká škola ekonomická v Praze, 2013. http://www.nusl.cz/ntk/nusl-193607.

Full text

Abstract:

The diploma thesis deals with definition of the main part of optimal portfolio of pharmaceutical company. The goal of the thesis is to identify top ten anatomical-therapeutic groups by sales, which can set up the main part of maximized sales portfolio. Approach of the diploma thesis is authentic strategic decision of man-agement of generic pharmaceutical company that penetrates Czech market. Dispensable materials for manager decisions consist of common access resources. Materials go with information about competition's sales, figures about the medication's movement in distribution chain and data of payer's costs. The decision will be made in simple one-criterion choice. The significance of the anatomical-therapeutic groups will be confirmed by epidemiological data.

APA, Harvard, Vancouver, ISO, and other styles

12

Zhao, Yang. "Business model evolution and firm performance of entrepreneurial companies." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7627/.

Full text

Abstract:

This research explores the business model (BM) evolution process of entrepreneurial companies and investigates the relationship between BM evolution and firm performance. Recently, it has been increasingly recognised that the innovative design (and re-design) of BMs is crucial to the performance of entrepreneurial firms, as BM can be associated with superior value creation and competitive advantage. However, there has been limited theoretical and empirical evidence in relation to the micro-mechanisms behind the BM evolution process and the entrepreneurial outcomes of BM evolution. This research seeks to fill this gap by opening up the ‘black box’ of the BM evolution process, exploring the micro-patterns that facilitate the continuous shaping, changing, and renewing of BMs and examining how BM evolutions create and capture value in a dynamic manner. Drawing together the BM and strategic entrepreneurship literature, this research seeks to understand: (1) how and why companies introduce BM innovations and imitations; (2) how BM innovations and imitations interplay as patterns in the BM evolution process; and (3) how BM evolution patterns affect firm performances. This research adopts a longitudinal multiple case study design that focuses on the emerging phenomenon of BM evolution. Twelve entrepreneurial firms in the Chinese Online Group Buying (OGB) industry were selected for their continuous and intensive developments of BMs and their varying success rates in this highly competitive market. Two rounds of data collection were carried out between 2013 and 2014, which generates 31 interviews with founders/co-founders and in total 5,034 pages of data. Following a three-stage research framework, the data analysis begins by mapping the BM evolution process of the twelve companies and classifying the changes in the BMs into innovations and imitations. The second stage focuses down to the BM level, which addresses the BM evolution as a dynamic process by exploring how BM innovations and imitations unfold and interplay over time. The final stage focuses on the firm level, providing theoretical explanations as to the effects of BM evolution patterns on firm performance. This research provides new insights into the nature of BM evolution by elaborating on the missing link between BM dynamics and firm performance. The findings identify four patterns of BM evolution that have different effects on a firm’s short- and long-term performance. This research contributes to the BM literature by presenting what the BM evolution process actually looks like. Moreover, it takes a step towards the process theory of the interplay between BM innovations and imitations, which addresses the role of companies’ actions, and more importantly, reactions to the competitors. Insights are also given into how entrepreneurial companies achieve and sustain value creation and capture by successfully combining the BM evolution patterns. Finally, the findings on BM evolution contributes to the strategic entrepreneurship literature by increasing the understanding of how companies compete in a more dynamic and complex environment. It reveals that, the achievement of superior firm performance is more than a simple question of whether to innovate or imitate, but rather an integration of innovation and imitation strategies over time. This study concludes with a discussion of the findings and their implications for theory and practice.

APA, Harvard, Vancouver, ISO, and other styles

13

Piboonrungroj, Pairach. "Supply chain collaboration : impacts and mediation on firm performance." Thesis, Cardiff University, 2012. http://orca.cf.ac.uk/47552/.

Full text

Abstract:

Purpose: The aim of this thesis is to explore the dimensions of supply chain collaboration and examine its impact on firm performance and its mediating variables. Methodology: A theoretical model was developed from a systematic review of relevant literature and theories. This was then revised by academics and practitioners. The model was empirically tested with survey data of 853 responses of tourism firms in Thailand using Structural Equation Modeling. Findings: Results indicate that supply chain collaboration improves firm performance. This impact is mediated by trust, commitment, transaction costs and sustained competitive advantage. A multiple group analysis supports the research model across four groups, however there are differences in the coefficients in some of the paths. In goodsbased transactions suppliers emphasises on collaboration to build relationships and to reduce transaction costs through developing commitment, while buyers focus on trust building. In the service-based transactions, service providers also tend to focus on trust as a key factor than service intermediaries who emphasises on developing commitment. Theoretical contribution: This thesis synthesised six theories to explain how supply chain collaboration affects firm performance. The constructs of supply chain collaboration and transaction costs are also improved. Managerial insight: The results inform managers about how different types of supply chain collaboration can improve the performance of their organisations. It also emphases the different mechanisms (i.e., trust and commitment) in supply chain relationships between goods-based and service-based transactions. Keywords: Supply Chain Management, Tourism supply chains, Sustained Competitive Advantage, Structural Equation Models, Thailand. JEL Classification 1 : C42, D2, L22, L25. 1Classification system by the Journal of Economic Literature, available at: http://www.aeaweb.org/jel/guide/

APA, Harvard, Vancouver, ISO, and other styles

14

Chang, Jieun. "Three Papers on Firm and Consumer Behavior in Online Markets." Thesis, University of Colorado at Boulder, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3561932.

Full text

Abstract:

My dissertation contains three empirical studies on firm and demand behavior in the U.S. high-speed Internet market. The first study examines the question that the probability of new entry varies with the characteristics of markets in which an incumbent firm is able to offer mixed bundling. Empirical findings present low entry rates in markets with high income and more years of schooling, because these markets are associated with low likelihood of switching. As the federal government aims to increase high-speed Internet access, more competition led by a new entry can increase high-speed Internet penetration and encourage the competitive provision of advanced high-speed Internet service.

The second study focuses on the relationship between Internet privacy concerns and offline businesses. The growth of online shopping has raised concerns about online privacy protection, which may lead consumers to be more likely to shop at offline stores. Empirical evidence suggests that Internet privacy concerns are positively related to the number of offline businesses, such as bookstores and travel agencies and the growth of offline businesses in the retail trade and the finance and insurance industries. This can provide interesting policy implications for local economies.

The third study examines two competing explanations regarding the demand for online health services: locations of consumers and the opportunity cost of time. The former expects that the longer distance to hospitals increases rural residents' demand for online health service, whereas the latter takes into account the possibility that urban residents whose valuations of time are high have a high demand for these services. This study finds that the demand for online health services does not vary with the location of consumers or the opportunity cost of time. The federal government has expanded this service in rural areas, which may provide limited benefits to these communities.

APA, Harvard, Vancouver, ISO, and other styles

15

May, Adam D. R. "Identification of fire gases in early stages of fire in laboratory scaled and full scale fire experiments." Thesis, University of Central Lancashire, 2011. http://clok.uclan.ac.uk/2823/.

Full text

Abstract:

A series of reduced scale emulations of standard fires in a 2 m3 enclosure have been developed for studies at laboratory scale enabling useful comparison and correlation with full scale EN54/7 and UL268 test fires. This makes study of standard test fire conditions and products substantially more accessible. The reduced scale test fire emulations have smoke obscuration characteristics matched to the fire standards and show acceptable matching of experimental CO levels Sensor, fire detector, and analytical studies have been carried out on test fires in the 2 m3 enclosure and in a full scale test room. Protocols were developed for capture of gas and vapours from fires on absorbent media and their subsequently desorption and analysis by GC/MS techniques. A data set of GC chromatograms has been generated for full and reduced scale test fires and for a number of non standard fire or false alarm related process including overheating of cooking oils and toasting bread. Analysis of mass spectrometry ion fragmentation spectra has been carried out and a wide range of products identified. Products occurring for a range of different fires include propene, benzene, and some polyaromatics. The value of the scaled test fire emulations has been demonstrated by monitoring response of a range of sensors, detectors and instruments including electrochemical gas sensor, experimental and conventional light scattering smoke detectors, and ion mobility measurement equipment (FAIMS). The study has provided information on fire characteristics and products to inform future research and development on fire detection technologies.

APA, Harvard, Vancouver, ISO, and other styles

16

Bequeath, Kristen M. "Family-Firm Leadership| A Case Study of an Organizational Family-Firm Leadership According to Bowen's Family Systems Theory and Lewin's Systems Theory." Thesis, Franklin Pierce University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3640146.

Full text

Abstract:

Family firms contribute to both the national and global economies. Over the last few decades, the family-business field has continued to develop, as have its counterpart disciplines of business, economics, psychology, and social sciences. The study of leadership theory has also advanced over the years; however, not much research has applied this theory to family firms.

This dissertation contains the oral histories of a family-owned manufacturing business that is still operating after 60 years. The purpose of this exploratory case study was to examine the leadership dynamics of a family operation. To provide a theoretical leadership model to understand the oral histories presented in this dissertation, four major themes were discussed: family systems theory, organizational psychology, leadership studies, and the manufacturing industry.

The shifts in scholars' understanding of organizational dynamics were presented using Bowen's family systems theory and Lewin's systems theory is detailed in the narrative portion. This study used two mechanisms to study the family firm: oral histories (captured through open-ended interviews) and written documents and memoirs. Excerpts of written narratives also ground the interviews within the firm's historical and geographical setting.

This study documents the significance in understanding organizational culture to the development of a leadership model for family firms. This case study provides the opportunity to identify key attributes within a successful family firm. This firm has remained successful through multiple leaders over several decades within a challenging industry.

APA, Harvard, Vancouver, ISO, and other styles

17

Kang, Kyoung-Lae. "Novel genres or generic novels considering Korean movies adapted from amateur Internet novels /." Connect to this title online, 2008. http://scholarworks.umass.edu/theses/96/.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Qurashi, Zahoor Ahmed. "A generic approach, employing information systems, for introducing manufacturing information systems in SMEs." Thesis, University of Plymouth, 2000. http://hdl.handle.net/10026.1/2836.

Full text

Abstract:

This thesis presents an approach which the small and medium size firms can use in-house to introduce manufacturing information systems. The approach developed is generic and employs information system design and analysis techniques to guide Small and Medium size Enterprises (SME's) from specification of their need, right through to the implementation of an appropriate solution. Although there are various tools and methodologies that are available for large organisations needs, none are available for SME's. Therefore, the approach presented in this thesis provides original and significant improvements on current practice. The approach emphasises the importance of taking a company wide approach to analyse systems throughout its various departments to establish bad practices and system flaws which may impinge on the performance of the manufacturing operations. The research involved three independent stages. The first stage was the identification of the problem which was realised from two sources: literature survey and interviews with case study company managers. The second stage was the development of a novel approach. The final stage included the validation of the approach by implementing it in five different SMEs in the Devon and Cornwall region. Through the use of this work, company's are encouraged to improve ownership and commitment to the manufacturing information systems by fully involving the relevant company personnel in identifying and resolving various problems. The approach proposed also helps managers understand how the various processes work in other areas of company, and can subsequently lead to improvements in other departments.

APA, Harvard, Vancouver, ISO, and other styles

19

Rhodes, Jennifer. "Fire protection of surface coatings." Thesis, University of Central Lancashire, 2012. http://clok.uclan.ac.uk/3738/.

Full text

Abstract:

Multilayer paint is a significant fire hazard particularly concerning rapid spread of flame,smoke and toxic species production. Fire protective coatings are often employed to protect this unpredictably flammable substrate from ignition (for example resulting from arson attacks in the communal areas of multi- occupancy buildings). Literature shows a gap in the understanding of this problem,a lack of suitable flammability tests,and methods for screening new fire protective coatings required to address this problem. This work investigates the factors affecting coating performance and develops screening test methods to estimate protection performance in standard fire tests. The dependence of these tests has been investigated with regard to substrate, coating thickness,composition of coating, thermal conductivity and rheological properties, to inform the development of modified coating formulations with enhanced fire safety.Coating materials have been investigated using thermogravimetric ana lysis (TGA) in both air and inert atmospheres and their burning behaviour using the cone calorimeter (ISO 5660). Novel screening test methods also include a test adapted from BS EN 367 for measurement of thermal conductivity, a thermocouple embedded in cone samples to assess the temperature profile at the substrate-coating interface and BS 476: Part 6 (adapted) as a scaled down version of the standard fire test. The chemical changes occurring during burning of current coatings formulations were investigated using CHN analysis, pyrolysis gas chromatography coupled with mass spectrometry (pyGC-MS),inductively coupled plasma coupled with mass spectrometry (ICP-MS),diamond attenuated total reflectance coupled with fourier transform infra-red (dATR-FTIR),nuclear magnetic resonance (NMR} and scanning electron microscopy coupled with electron dispersive X-ray analysis (SEM-EDAX} to inform the development of novel formulations. Generally,intumescent formulations tend to exhibit lower fire propagation indexes when assessed in the BS 476: Part 6,longer time to ignition and lower peak heat release rates in the cone calorimeter, as well as reduced thermal conductivity recorded in the BS EN 367. Results report mixed performance,suggesting that it is not only char residue formation that ensures a pass in the standard fire tests. Rheological properties of the coatings are crucial to performance,with softening temperature and reduction in viscosity coinciding with gas release of the fire retardant additive. Each screening test method assesses one particular aspect of flammability, they are dependent on the controlled conditions under which results are collected,and the limited correlation observed with the performance in the standard fire tests, do not conclusively predict performance in a real fire situation.

APA, Harvard, Vancouver, ISO, and other styles

20

Hibert, Sanchez Abel Mauro. "A dominant firm strategy and its effect on the capital structure of non-dominant firms in the self service discount stores industry and auctions for radio spectrum to mobile services in Mexico." Thesis, Instituto Tecnologico y de Estudios Superiores de Monterrey (Mexico), 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3585550.

Full text

Abstract:

In an industry characterized by oligopolistic market structures there are generally firms that have enough market power as to influence the pricing and output decisions of all participants, forcing others to follow the strategies decided by the dominant firm(s) with very little opportunity to do otherwise (Besanko et al 2010, Tirole 1990). When a dominant firm is at the same time part of a larger corporation, and due to the financial support it is likely to have from its parent, it has the capacity to support an above-average, constant long-term investment strategy as a logical reaction to protect (or minimize) the loss of market share, and the rest of the participants in the industry are expected to also make an attempt to increase their investments, permanently affecting their long-term capital structure strategy (Chevalier 1995). This dissertation’s contribution to the literature in the field consists on presenting an empirical analysis of the capital structure decisions of the non-dominant firms in the Self-Service Discount Stores Industry (SSDSI) that result from the rapid expansion of Wal-Mart in the Mexican market, as well as an empirical analysis of the investment decisions in radiofrequencies of the incumbents firms in the capital structure of the other firms in the Mobile sector in Mexico.

Keywords (Industrial organization, Economics of Strategy, market structure, oligopolistic competition, capital structure, conditioned investment, market concentration, supermarket sector, spectrum auctions).

APA, Harvard, Vancouver, ISO, and other styles

21

Wang, Miao. "The effects of government subsidies on firm innovation : evidence from China." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/53677/.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Jones, Matthew. "Becoming 'film noir' : film noir adaptions of hard-boiled fiction, 1944-46." Thesis, University of Wales Trinity Saint David, 2018. http://repository.uwtsd.ac.uk/900/.

Full text

Abstract:

This thesis interrogates a number of issues that surround what critics have designated ‘film noir’ and its relationship to that branch of modern American literature identified as ‘hard- boiled fiction’. Thus, the main subject matter for the thesis consists of selected films noirs from 1944—46, and the novels of Dashiell Hammett, James M. Cain, and Raymond Chandler. The thesis argues that the adaptation process is of central significance to the ‘film noir’ debate and to film noir itself. While it argues for a dialogic exchange between ‘noir’ and ‘hard-boiled fiction’, it proposes as well that there was also a fundamental incompatibility between the two modes. The thesis discusses the difficulties encountered by Hollywood studios in adapting Cain’s work due to the candid representation of ‘adult’ themes, and how this conflicted with Hollywood censorship, carried out by the Production Code Administration (PCA). In order for Cain’s fiction to be adapted, it is argued, Hollywood conventions regarding the representation of sex and violence and the PCA guidelines by which they were governed had to undergo radical change. The critical and scholarly contexts for this argument include debates concerning influence, censorship, and the involvement of the PCA with the adaptation process, and the notion, as maintained by elements within the revisionist debate, that ‘film noir’ has no conceptual or theoretical basis. The thesis challenges revisionist arguments that ‘noir’ was ‘invented’ by French critics in 1946, and argues that although the genre was named retrospectively, generic practice was established by Hollywood producers in acts of ‘applied criticism’ prior to production, from around 1944 onwards. The thesis contextualises the generic practice of ‘noir’ within the history of film, while arguing simultaneously for historic changes in Hollywood film-making of the mid-1940s in terms of the representation of ‘adult’ themes, and the relaxation of the Production Code. The thesis discusses how criticism has tended to privilege other media, such as the plastic arts and literature, over film, and argues that notions of artistic style and influence must give consideration to the immanence of the film production context. The notion that ‘noir’ was influenced by the artistic movement known as ‘German Expressionism’ has been questioned by the revisionist debate. The thesis examines and discusses key German films of the Weimar period, when the artistic movement ‘Expressionism’ flourished, arguing that the Weimar influence is discernible in the generic practice of ‘noir’. However, the thesis makes a case that this is, primarily, the legacy of Weimar cinema, and that the influence of ‘Expressionism’ should be discussed within this medium-specific context. The thesis examines the connections between the work of a number of influential directors and the signifying practice of ‘noir’, including Murnau, Lang, Hitchcock and Hawks. It is proposed that certain ‘noir’ conventions can be traced back to the work of these influential directors. The thesis proposes a way of understanding ‘film noir’ as a genre, and argues that the adaptation process needs to be seen as a nexus for various discourses, including directorial style, screenwriting, cinematography, the studio system, and censorship, in addition to the relationship between the film and the novelistic text.

APA, Harvard, Vancouver, ISO, and other styles

23

Anderton, Dane. "Firm ecologies : life science and video game industries in Liverpool." Thesis, University of Liverpool, 2014. http://livrepository.liverpool.ac.uk/2009228/.

Full text

Abstract:

This research examines the life science and video games industries in Liverpool. Previous research on agglomerations and cities tends to focus on epicentres or high concentration places such as Silicon Valley or global cities such as London and Tokyo, neglecting the northern post-industrial cities such as Liverpool, Leeds or Newcastle. Equally, many studies tend to focus in on one particular industry, whereas this research examines two key knowledge economy sectors in one place. Petilis (2012) argues that the cluster literature has become overemphasised and lacks analytical ability in the investigation of smaller firms and highly diverse concentrations of activity. An alternative ecological perspective is used in this thesis, which is considered more reflexive and flexible to the composition of the agglomerations seen outside the epicentres of the global economy. Using the heterarchical approach, as outlined by Grabher (2001), this research investigates the emergence and organisation of Liverpool’s life science and video game industries. It reveals the changing composition of the industries in Liverpool and how firms are connected into wider production networks beyond Liverpool. Finally, the research analyses how the two industries are situated in the anatomy of the city. The key findings are generated from a mixed methodology utilizing qualitative semi-structure interviews with owner-managers, industry informants and supporting institutions. Secondary quantitative data has been used gathered from annual reports, company websites, industry association and office for national statistics. Firstly, it is argued that the two industries emerged in Liverpool under different conditions and are on different trajectories, conditioned by local events and global mechanisms in the wider industry. Such trajectories have aided the rise or the fall of various structures and institutions within the city of Liverpool. This has resulted in a life science industry that resembles an institutionally thick anatomy and a video games industry that resembles an institutionally thin anatomy. Secondly, key findings regarding the organisation and connections beyond Liverpool highlight the fact that both industries show a lack of internal connectivity within the ecology and depend significantly on their external connections for inputs in production. For the life sciences this is exacerbated with the high level of product diversity between firms decreasing the likelihood of potential internal connectivity in production or joint resource utilization between firms. Thus firms rely on their external connections for finance and resources in order to further the production of their products through licensing and merger and acquisition agreements. Thirdly, the video games industry has gained greater autonomy over production analogues to that of the industry norm. For the life sciences, the rigidity in the generic business model is reinforced by the high levels of regulation and intellectual property protections and reduces the ability of some smaller firms to complete a product. Overall, we see two key knowledge economy sectors emerging with changing degrees of functionality as a result of global changes in the industry and the development of institutional infrastructures around these two sectors.

APA, Harvard, Vancouver, ISO, and other styles

24

Nichol, Linda J. "Spin-offs and new firm formation entrepreneurship and high technology in the Ottawa area." Thesis, University of Ottawa (Canada), 1985. http://hdl.handle.net/10393/4767.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Renaud, Jean-Louis. "An analysis of costless stockpiling by the resource extracting firm under various market structures." Thesis, University of Ottawa (Canada), 1987. http://hdl.handle.net/10393/5410.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Ennis, Larissa, and Larissa Ennis. "Melodramas of Ethnicity and Masculinity: Generic Transformations of Late Twentieth Century American Film Gangsters." Thesis, University of Oregon, 2012. http://hdl.handle.net/1794/12333.

Full text

Abstract:

Larissa Ennis Doctor of Philosophy Department of English March 2012 Title: Melodramas of Ethnicity and Masculinity: Generic Transformations of Late Twentieth Century American Film Gangsters The gangster film genre in America has enjoyed a long history, from the first one-reelers

APA, Harvard, Vancouver, ISO, and other styles

27

Hoffmann, Nicole Andrea. "Computer simulation of fire-sprinkler interaction." Thesis, University of Greenwich, 1990. http://gala.gre.ac.uk/6369/.

Full text

Abstract:

The research work presented herein addresses the problem of the mathematical modelling of fire and fire-sprinkler scenarios. This involved the numerical simulation of two-phase, three-dimensional, buoyant, turbulent, recirculating flows. The simulations were carried out in two successive and distinct stages. The first stage dealt with the modelling of buoyant hot turbulent gas flows generated by a fire within room-sized compartments. These single phase studies were based on the field modelling approach to fire simulation. The second part of the study involved the introduction of the cold water droplets through a single sprinkler head, thus, extending the scenario into the more complex two-phase regime. This led to expanding the single-phase fire model to take account of two concurrently present phases, ie. gas/liquid. The strategy used to model the twophase process was the Eulerian-Eulerian technique or volume-fraction method. In order to take into account the physics involved in this process, interphase friction or drag was considered. Furthermore, due to the large difference in temperatures between the hot gases and the cold water droplets it was necessary to introduce interphase heat transfer. Due to the subsequent evaporation of the water droplets interphase mass transfer was also accounted for. Models for both steady-state and time-dependent situations were developed, whereby experimental results of transient fire-sprinkler tests were used for validation. The simulations performed indicated the creation of extremely complex flow fields within the compartments both prior and during sprinkler activation. Phenomena such as the significant cooling of the hot combustion gases caused by the active sprinkler and the evaporation of water droplets have also been predicted. This has been verified by the experimental data. Thus, it can be concluded that the models outlined herein are capable of simulating the complex two-phase fire-sprinkler scenarios. The need for subsequent investigative studies into such areas as the effect of using different auxiliary relationships eg. heat transfer, sprinkler characteristics and gridspacing has been highlighted. In order to complete the validation process, further experimental data needs to be made available. This two-phase technique has proven to be very computationally intensive with simulations requiring days of CPU time. 'Mis is clearly unacceptable. However, it is suggested that parallel computing technology may provide a means for reducing the CPU time involved to hours. It can be concluded that though the model developed requires further investigation and refinements, it provides a basis for a practical and useful fire engineering tool.

APA, Harvard, Vancouver, ISO, and other styles

28

Fleming, Cameron. "Vita activa and the nature of economic enterprises: a political theory of the firm." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114614.

Full text

Abstract:

This thesis considers whether the contemporary capitalist firm can be understood in political terms independent of its association with the broader economic or political systems within which it is located. Viewed through an Arendtian framework of the Athenian polis and vita activa - and its Aristotelean connection between necessity and unfreedom - it becomes possible to understand the firm in such a manner. The modern elevation of the economic role of the household to the level of society - concomitant with the emergence of government as administration - results in the social, rather than individual, production of the satisfaction of biological necessity. This development makes it possible to question Arendt's assertions regarding the antipolitical nature of the labourer (animal laborans) and the apolitical nature of the worker (homo faber), thus opening the way for a resumption of political eligibility for citizens. However, because of the rise of the social and its associated gigantism, there does not seem to be a properly political space where animal laborans and homo faber can exercise these political capacities. This thesis proposes that such a political space can indeed exist, albeit in an unorthodox and unexpected location. By looking to a model of the Athenian polis which draws its inspiration from the thought of Hannah Arendt, it is thus possible to reconceptualize the economic enterprise as a private polis inhabited by worker-citizens.
Cette thèse considère que l'entreprise capitaliste contemporain peut être compris en termes politiques indépendants de son association avec les grands systèmes économiques ou politiques au sein duquel il est situé. Vue au travers d'un cadre d'Arendt de la polis athénienne et vita activa - et sa connexion aristotélicienne entre la nécessité et la non-liberté - il devient possible de comprendre l'entreprise dans une telle manière. L'élévation moderne du rôle économique du ménage au niveau de la société - concomitante avec l'émergence de l'État comme l'administration - se traduit par la production sociale plutôt qu'individuelle, de la satisfaction de la nécessité biologique. Ce développement permet de remettre en question les affirmations de Hannah Arendt sur la nature antipolitique de l'ouvrier (animal laborans) et le caractère apolitique de l'ouvrier (homo faber), ce qui pourrait ouvrir la voie à une reprise de l'éligibilité politique pour les citoyens. Cependant, en raison de la hausse du social et de son gigantisme associé, il ne semble pas y avoir un espace proprement politique où des animal laborans et homo faber peut exercer ces capacités politiques. Cette thèse propose qu'un tel espace politique peut effectivement exister, mais dans un endroit peu orthodoxe et inattendu. En regardant vers un modèle de la polis athénienne, qui puise son inspiration dans la pensée de Hannah Arendt, il est ainsi possible de redéfinir l'entreprise économique comme simple soldat polis habitée par des travailleurs-citoyens.

APA, Harvard, Vancouver, ISO, and other styles

29

Ovčačík, Miroslav. "Návrh konkurenční strategie firmy." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2009. http://www.nusl.cz/ntk/nusl-222099.

Full text

Abstract:

The aim of this work is propose competitive strategy of Stytotrade company. It is divided into three segments: theoretic part, analytical part and project part. The theoretical part present the company and literary sources that deal with strategies of competitive advantage, Porter generic strategies, theory knowledge of competition, marketing research and strategy for market leader. Analytical part is focused on the identification of competition, macro environment, current corporate strategy, marketing mix and marketing research. Project part - data from the marketing research are processed to SWOT analysis that is fundation for the propose of competitive strategy.

APA, Harvard, Vancouver, ISO, and other styles

30

Waschneck, Katja. "Screening 'Oulipo' : from potential literature to potential film." Thesis, University of Essex, 2018. http://repository.essex.ac.uk/22413/.

Full text

Abstract:

This thesis documents a research and art project that explores the creative value of using constraints in film. The starting point is the Ouvroir de Littérature Potentielle (Oulipo), the Potential Workshop of Literature, whose members explore the Potential of Literature by writing with constraints, and the films of the early twentieth century avant-garde, which demonstrate the promise of experimentalism in cinema. From these points of inspiration, the idea of using constraints to explore the potential of a field is transferred to film. As the practice of filmmaking with constraints is yet to be fully formalised and currently lacks substantial academic recognition, this thesis presents a theorisation of constraint filmmaking as a creative practice that cuts across cinematic genres and already established areas of filmmaking practice – those of short, feature, and documentary film. The cinematic work emerging from the Ouvroir de Videographie Potentielle (Ouvipo), the Potential Workshop of Video, and the movement of Dogme 95, are shown to be influential in the theorisation of constraint filmmaking practice, and several other examples of constraint films across cinema will be addressed to show how the use of constraints can enhance a filmmaker’s creativity. The thesis is accompanied by three constraint films: Project Cube, A Day in your Life, and Tales and Tellers, which were made in adherence to the stages of the constraint filmmaking process. Project Cube is an exploration of mathematically inspired constraints and is grounded in the idea of permutation. Twelve shots are used to create several different films, with their order being determined by the rolling of dice. A Day in Your Life focuses on the interplay between linguistic constraints and their visual counterparts, reality and fiction, and past and present. Tales and Tellers is a project that shows the power of images, as fairy tales from participants are illustrated in moving images, using constraints to create these pictures. These short films demonstrate both my theorisation of constraint filmmaking as a practice that can be adopted by other artists also, and my journey from Potential Literature to Potential Film.

APA, Harvard, Vancouver, ISO, and other styles

31

Liu, Kuang-Tai. "ALTERNATIVE GENERIC STRATEGIES STUDY FOR SMALL AND MEDIUM SIZE FIRMS IN TAIWANESE ELECTRONIC MANUFACTURING INDUSTRY." NSUWorks, 2010. http://nsuworks.nova.edu/hsbe_etd/65.

Full text

Abstract:

The economy of Taiwan relies heavily upon the electronic manufacturing industry; hence choosing appropriate generic business strategies which are consistent with the environment based on suitable resources can allow small and medium size firms to sustain their competitive advantages and earn a higher return for the electronic manufacturing industry in Taiwan. This study intensities the effect of the precedent factors and generic business strategies chosen on the performance of small and medium size firms in the Taiwanese electronic manufacturing industry. It explores simultaneously the impact of the resources and the environment on business strategy which affects a firm's performance will provide valuable insight into the formulation of competitive strategies by structural equation modeling (SEM) technique. Finally, the use of SAS 9.0 with Amos 5.0 perform first order confirmatory factor analysis for the reliability of questionnaire and explores the relationship among variables in the proposed model based upon path analysis and multiple regression statistical methods and to recommends a new model depending on survey data gathered from firms in Taiwanese electronic manufacturing industry.

APA, Harvard, Vancouver, ISO, and other styles

32

Rebegea, Simina Aurelia. "Nanosecond laser ablation of thin film material libraries." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8555/.

Full text

Abstract:

This work offers a novel approach to the investigation of material response in nanosecond laser ablation, by irradiating a thin film material library (having small variations in the chemical composition) with a beam of constant parameters. The method could be used as a way to assess the machining capability of a wide range of materials. Single-pulse craters were obtained with nanosecond infrared lasers (Nd:YAG, 1064 nm, 30-55 ns). The influence of reflectivity, thermal properties, surface and sub-surface morphology of the target material are correlated with the variations in crater geometry, morphology and the amount of removed material. Pure Cu, Al and Ni films and their binaries were studied to establish typical craters and to illustrate how a change in the parent material affects the workpiece after irradiation respectively. The study of the ternary compositional gradients irradiated with constant laser parameters extends upon these findings, and represents, to this point, the first work of its type. A second film (Cu-Al-Zr) was analysed to confirm that the variations in crater geometry and morphology were not material-specific. It is also shown that nanosecond laser ablation of thin films (with minimal thermal damage to the substrate) can be achieved with a typical Gaussian beam.

APA, Harvard, Vancouver, ISO, and other styles

33

Ahmed, Rita Maqsooda. "Micromagnetic modelling of thin film media." Thesis, University of Central Lancashire, 2001. http://clok.uclan.ac.uk/7911/.

Full text

Abstract:

The magnetic recording industry is continuously trying to increase the density of recording media. There is a continuous need, therefore, to fully understand the magnetic processes that occur in such media. To enable this understanding, theoretical studies are conducted in the form of micromagnetic modelling. This thesis is concerned with the micromagnetic modelling of thin film media. Experiments have shown that thin film media consists of closely packed, irregularly shaped grains with non-magnetic boundaries. To simulate a model of the physical structure, the Voronoi Construction Technique was implemented to give the required irregular structure. The grains were assumed to have uniaxial anisotropy and the magnetisation within the grain was assumed to vary throughout. To achieve non-uniformity, the grains were divided into triangles and the magnetisation within each triangle was assumed to vary linearly. The effect on the magnetisation within the grains due to the influences from an externally applied field, an anisotropy field, a magnetostatic field and an exchange field was observed. The motion of the magnetic moments under these influences was modelled by the Landau-Lifshitz equation. The most time consuming calculation in the modelling process is the magnetostatic field calculation. Therefore, continuous research into more efficient methods of calculating this field is carried out. The model initially uses a dipole approximation to calculate the total contribution from the magnetostatic field. A more accurate magnetostatic calculation, based on volume and surface charges of the triangles, was implemented to calculate the close range magnetostatic effects. The integrals were found to have singularities when the point of evaluation lay on one of the vertices of a triangle to be integrated. The Shift Method was introduced to overcome the problem which translated the problem vertex slightly away from the point of evaluation. Vast differences in the hysteresis loops when using the two methods of calculating the magnetostatic field were seen. The dipole approximation appeared to be too inaccurate in calculating the magnetostatic field. With the introduction of the more accurate method, the model compared well against previous findings.

APA, Harvard, Vancouver, ISO, and other styles

34

Lawrence, Megan Lynn. "Why Do Firm Practices Differ? Examining the Selection and Implementation of Organizational Practices." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:32744397.

Full text

Abstract:

This dissertation is comprised of three studies investigating sources of variation in firm practices. Firm practices may differ both due to differences in the practices firms choose to implement – different types of firms may make different selections – and due to differences in implementation success of similar practices – variation in internal firm conditions may result in differences in otherwise similar practices. The first essay examines a difference in firm practice selection whereas the second and third essays examine differences in firm practice implementation. Essay one considers how ownership impacts the management practices implemented by firms, specifically considering the founder CEO firm’s adoption of management practices as compared to firms with other owner-manager types. Founder CEO firms adopt fewer management practices than firms under other ownership structures, both due to a lack of awareness about the lower quality of their practices and due to greater value placed on the nonpecuniary benefit provided by potentially less efficient but power-preserving practices. Essays two and three use data from a Fortune 100 retail chain that implemented a new restocking practice across a subset of its retail stores. Essay two examines how prior experience with the old restocking practice impacts a team’s ability to perform and learn the new restocking practice. Teams with greater exposure to the old practice perform worse at first – due to experiencing a competency trap – but then improve more rapidly – due to greater efficiency of communication and coordination. Essay three focuses on the impact of pilot use when rolling out the new practice, proposing that a main function of pilot implementations is to allow for vicarious learning opportunities for stores subsequently implementing the practice. The relative performance of the pilot stores as well as the contextual similarity of these stores to the stores learning from them matters a great deal. Nonpilot stores increasingly rely only on their own experiences rather than the pilots’ experiences in instances where the learning opportunities become less obvious.

APA, Harvard, Vancouver, ISO, and other styles

35

Nama, Samia. "The numerical modelling of composite floors exposed to fire." Thesis, City University London, 2008. http://openaccess.city.ac.uk/8590/.

Full text

Abstract:

This thesis deals with the influence of fire on the behaviour of steel concrete composite floors. A theory has been developed to calculate deflections during the fire and the ultimate strength of the composite floor under such conditions. The solution is based on the finite difference method. It takes temperature-dependent material properties into account. The method of analysis comprises two parts; the first is thermal analysis, enabling temperatures to be calculated as a function of fire exposure time. The second is strength analysis for calculating the strength of composite floor with material properties affected by temperature. For the heat flow analysis, the cross-section is divided into mainly rectangular elements. Sloping boundaries are approximated by triangular elements. The heat transfer from the fire to the surface is considered as well as heat conduction to the neighbouring points. At internal points, heat conduction to all the neighbouring points is considered. To calculate the deflections, the floor is divided into a two-dimensional mesh. The deflections are calculated for each mesh point based on orthotropic plate theory. The differential operators are replaced by the finite difference formulae. This reduces the governing differential equation into a system of linear algebraic equations. To calculate the plate rigidities, it is necessary to find curvatures for all mesh points in the two planes using finite difference operators. The thermal strains are superimposed on the mechanical strains associated with curvatures to find the net strains, and then stresses are calculated using the non-linear temperature dependent stress-strain curves. Integrating the stresses, the internal stress resultants are calculated. The above method has been programmed in Visual Basic. To validate this method, a comparison with a number of fire tests has been carried out, for both thermal and mechanical behaviour. The temperatures at comparable points are generally close to each other. Comparisons have also been carried out for calculated mid-span deflections by this method and the published test results. The results show excellent correlation between the tests and the new method. A parametric study has been carried out on floors with different boundary conditions when subjected to in-plane forces for two fixed and simple ends. Comparison of mid-span deflections between the fixed and simple end conditions has shown that fixed edges have better fire resistance than simply supported when not subjected to in-plane forces. It has found that in-plane forces had little effect on deflection rates at initial stages of the fire. These only appeared at later stages. When subjected to in-plane forces in one direction only the floor showed better response. The conclusion from the parametric study is that in-plane forces at different edges play a significant role in the behaviour, as the surrounding structure provides restraint increasing the fire resistance of the structure within the fire compartment.

APA, Harvard, Vancouver, ISO, and other styles

36

Yang, Xiaobo. "Numerical study of film cooling in hypersonic flows." Thesis, University of Glasgow, 2002. http://theses.gla.ac.uk/2063/.

Full text

Abstract:

In this thesis, a numerical study of film cooling in hypersonic laminar and turbulent flows has been performed using an in-house Navier-Stokes solver. The aim of this computational work is to investigate the mechanism and effectiveness of film cooling in hypersonic laminar and turbulent flows. Hypersonic flow over a flat plate without film cooling was first studied to provide a reference datum to check the effectiveness of film cooling. For laminar film cooling (M¥ = 9.9), three different primary flow conditions were first used for validation. The inclusion of the development of the flow in the plenum chamber upstream of the slot was found to provide better heat prediction than a uniform boundary condition at the slot exit. Detailed information of the flow field including velocity profile, Mach contour, temperature contour and heat transfer rate was presented. The mechanism of film cooling has been revealed according to the plots of calculated velocity profiles, Mach contours and temperature contours downstream of the slot. The coolant fluid was found to affect the primary boundary layer in two ways: 1) initially a separate layer established by the coolant fluid itself in the near slot area, 2) later a mixing layer between the primary and coolant flow streams. Then five coolant injection rates between 2.95 x 10-4 and 7.33 x 10-4kg/s and three slot heights 0.8382, 1.2192, 1.6002 mm, were examined in hypersonic laminar film cooling. For turbulent film cooling (M¥ = 8.2), for the geometry used in the experiment, the injection at an angle of 20° was found to be appropriate. Different turbulence models including Wilcox's k - w model. Menter's baseline and SST model have been tested. It is concluded that the Wilcox's k - w turbulence model with dilatation-dissipation correction provides the best heat prediction. Again, five coolant injection rates varies from 5.07 x 10-4 to 30.69 x 10-4 kg/s and three slot heights (the same as studied in the laminar film cooling) were studied to check the influence on film cooling effectiveness. Both the coolant and the primary flow were air. Film cooling was found to be an effective way to protect wall surfaces that are exposed under a high heat transfer environment especially in hypersonic laminar flow. Increasing the coolant injection rate can obviously increase the film cooling effectiveness. Again, this works better in laminar flow than in turbulent flow. The coolant injection rate in turbulent flow should be considered to be high enough to give good heat protection. Slot height in both laminar and turbulent flows under the flow conditions in this study was found to be less important, which means other factors can be considered in priority when constructing film cooling systems. With the application of curve fitting, the cooling length was described using power laws according to curve fitting results. A two-equation film coating model has been presented to illustrate the relation between the film cooling effectiveness and the parameter x/(h/m). For film cooling effectiveness in log-log coordinates, a second-order polynomial curve can be used to fit the laminar flows, whilst a straight line is suitable for the turbulent flows.

APA, Harvard, Vancouver, ISO, and other styles

37

Rubadiri, Lindiwe. "Evacuation modelling of mixed-ability populations in fire emergencies." Thesis, University of Central Lancashire, 1994. http://clok.uclan.ac.uk/1704/.

Full text

Abstract:

UK statistics have shown that a significant percentage of fatalities in fires have suffered from some kind of disability. In this context 'disability' relates to a person's physical or mental condition that impinges on their ability to react and move promptly in an emergency. Various evacuation modelling techniques are being adopted to study the movement of occupants during emergencies since the exposure of people to fires for experimental purposes is unethical. However, many evacuation models have ignored the effects of disability on escape potential and therefore tend to predict optimal evacuation times. Moreover, whilst providing some valuable insights into certain factors affecting occupant movement, current models are generally presented in isolation and fail to define a general framework for designing solutions to fire safety engineering problems. The purpose of this research programme was to develop a more general methodology for predicting evacuation times of mixed-ability populations. This was made possible through the development and use of a novel concept of evacuation peiformance index (EPI), which is the relative ease of evacuating a disabled person compared to an able-bodied person, founded on a consideration of the effects of disabilities and mobility aids on evacuation times. The author shows how this concept relates three aspects of fire safety, namely, individual characteristics of disabled occupants, the amount of assistance they require, and building design and environmental factors. She contends that the evacuation peifornzance index of a class of individuals is primarily dependent on these three categories. Experimental data to verify the above claim was collected from careflully monitored evacuation drills involving a group of disabled people. Their EPIs were determined along a pre-defined route from which their evacuation times were calculated. Comparisons between predicted times using the EPI concept and measured times from alternative empirical data were seen to be in reasonable agreement. An iterative design procedure is also suggested; one that is capable of predicting worst possible evacuation times by incorporating measures of EPI and escape route dimensions and details. The EPI concept provides fire safety engineering with a logical design philosophy, which is flexible and easily comprehensible. It endeavours to increase understanding of evacuation of disabled people, and provide a simplified mechanism for fire safety design and planning of evacuation procedures.

APA, Harvard, Vancouver, ISO, and other styles

38

González, David Muñoz. "Discovering unknown equations that describe large data sets using genetic programming techniques." Thesis, Linköping University, Department of Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2639.

Full text

Abstract:

FIR filters are widely used nowadays, with applications from MP3 players, Hi-Fi systems, digital TVs, etc. to communication systems like wireless communication. They are implemented in DSPs and there are several trade-offs that make important to have an exact as possible estimation of the required filter order.

In order to find a better estimation of the filter order than the existing ones, genetic expression programming (GEP) is used. GEP is a Genetic Algorithm that can be used in function finding. It is implemented in a commercial application which, after the appropriate input file and settings have been provided, performs the evolution of the individuals in the input file so that a good solution is found. The thesis is the first one in this new research line.

The aim has been not only reaching the desired estimation but also pave the way for further investigations.

APA, Harvard, Vancouver, ISO, and other styles

39

Matellini, Dante Benjamin. "A risk-based fire and rescue management system." Thesis, Liverpool John Moores University, 2012. http://researchonline.ljmu.ac.uk/6187/.

Full text

Abstract:

This PhD focuses on developing a risk-based fire and rescue model for dwelling fires which importantly, is where most fire deaths occur each year. There are a vast number of variables to consider when modelling dwellings, for example variations will arise in terms of geographical location, fire safety arrangements, characteristics of occupants, activities of occupants, among others. As for the occurrence of fire itself, each incident will be unique in terms of time of day, type of fire, state of occupants, fire cues, etc. What all these variations signify is that the potential magnitude of the next fire event and its consequences are generally unpredictable. Because of complicated scenarios, unpredictability of outcomes, and high frequency of incidents, Fire and Rescue Serices (FRS) have to be both capable and flexible in operation; however finding the optimal way of providing emergency cover and minimizing risk is a complicated task which often results in reasoning and decisions taking place under uncertainty. In order to diminish some of this uncertainty and improve confidence in decision making, an extensive four-part Bayesian Network (BN) model is developed focusing on dwelling fires within the UK. The intention is to model the sequence of events which may occur during a fire from ignition through to extinguishment with the objective of assessing, under specified conditions, fire safety at a given location; this should assist in determining what the most important safety issues are for the purpose of improving fire prevention and mitigating consequences in order to reduce fire risk across residential communities. The model itself is broken down into four parts which can function independently or together as an integrated network. The model parts are as follows: Part I - "Initial fire development". Part II - "Occupancy response and further fire development". Part III - "Advanced fire situation and consequences". Part IV - "Fire response time module". Within the project a risk-based fire and rescue operations management framework is also presented to demonstrate how the BN model could fit into the strategic management of FRS's and how it could link up with other tools and data collection programmes. The BN model may prove to be useful for strategic decision making within FRS's.

APA, Harvard, Vancouver, ISO, and other styles

40

Wang, Zhaoning. "Essays on Development Economics: Consumers, Firms, and Financial Institutions." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:33493388.

Full text

Abstract:

This dissertation presents three chapters addressing issues pertaining to consumers, firms, and financial institutions in the developing world. The first chapter, co-authored with Juan Ma and Tarun Khanna, evaluates the effect of voluntary information disclosure in incentivizing firms to deliver high quality in the absence of regulation. We present evidence from two field experiments in China’s infant milk powder industry, which is undergoing a serious consumer trust crisis after several safety scandals. Contrary to common beliefs, our results suggest that providing certain positive quality-related information has a significantly negative impact on consumers’ purchase decisions and impression of the industry. We explain our findings via the existence of a “reminder effect,” where information disclosure triggers recall of and diverts attention to health and safety risks related to certain products. In the second chapter, I study the impact of firms’ industrial diversification on their innovation outcomes in China, which has recently been an important topic due to various government initiatives. By exploiting a policy launched by the Chinese government since 2011, I estimate the impact of related and unrelated diversification on corporate innovations measured by the number of patents received after 2012. Overall, I find opposite results for production-oriented and service-oriented firms, with related diversification more effective for the former and unrelated diversification more effective for the latter. One explanation, which is supported by subsequent analysis, is related to the different degrees of transferability of the technology and knowledge required for innovations. In the third chapter, I examine the complementarity of formal and informal finance represented respectively by banks and bidding ROSCAs (Rotating Savings and Credit Associations) in India, a critical source of credit for many impoverished individuals, households, and small businesses. Different from some traditional views, my results suggest that formal financial institutions can benefit the informal ones instead of replacing them. Using auction data from ROSCAs and operational data from banks in Andhra Pradesh, India from 1998 to 2000, I find that the emergence of formal finance, measured by nearby bank openings, increases ROSCA participation, reduces the cost of capital for ROSCA participants, and lowers the amount of ROSCA default.
Economics

APA, Harvard, Vancouver, ISO, and other styles

41

Anderson, Graeme. "Design of high efficiency loudspeakers for use in fire alarms." Thesis, University of Southampton, 1997. https://eprints.soton.ac.uk/47542/.

Full text

Abstract:

Much work has been carried out into the operation of loudspeakers for use in audio applications. This thesis examines loudspeaker operation from an alternative point of view. For use in fire alarms, the loudspeaker is required to produce as much sound power as possible at a particular frequency whilst being as efficient as possible. The moving coil loudspeaker is used as a starting point due to its widespread use. Many papers describing its operation are available and as such is a good loudspeaker with which to examine modelling techniques. An impedance model of the moving coil loudspeaker is developed and shown to be a good simulation of its operation. The loudspeaker currently used in fire alarm units is the balanced armature loudspeaker. A lumped parameter model of this loudspeaker is developed using SIMULINK. Results from this simulation are compared with experimental measurements to verify the accuracy of the model. A new design of loudspeaker is then described. The modelling technique developed for the balanced armature loudspeaker is then applied to this design. The results again compare well to experimental measurements. The effect of varying the acoustic loading on each loudspeaker is considered along with an overview of the piezoelectric sounder. The thesis concludes with a discussion of the use of each loudspeaker in fire alarm units along with suggestions for possible design improvements implied by the models.

APA, Harvard, Vancouver, ISO, and other styles

42

Jabir, Saad A. A. "Thick film electronic ceramic sensors for civil structures health monitoring." Thesis, Edinburgh Napier University, 2011. http://researchrepository.napier.ac.uk/Output/4475.

Full text

Abstract:

Buildings, roads, bridges and structures in general suffer many kinds of damages due to overstress caused by settlements of foundations, high winds, dynamic forces, passing traffic, vibration and unexpected external loads beyond the safe design forces. The damages manifest itself by cracks, falling of plaster and render uneven roads and some time complete collapse. The cost of maintaining and fixing damages caused by the above is quite high for the building and construction industry. The same phenomenon is common to many other structures like airplanes, wind turbine and machinery in general. Structural Health Monitoring (SHM) is the engineering branch, which aims to give, at every moment during the life of a structure, a diagnosis of the "state" of the constituent materials, of the different parts of a structure. The state of the structure must remain in the domain specified in the design, although this can be altered due to usage or due to normal aging by the action of the environment, and by accidental events. By using special electronic sensors to monitor the unexpected high concentration of stresses or changes of these stresses throughout the life of the structure and pavement, reduces the cost of maintenance and repair. Historic buildings would also benefit from using such sensors to monitor the overstress in the old and frugally stones and bricks. The sensors can be embedded in the lime mortar joints and an electronic meter is used periodically to check for any unusual overstress during the life of the building. The main aim of the proposed research project is to investigate the possibility of using thick-film technology stress sensors in masonry, concrete and building materials in general to monitor overstress and instability throughout the life of the structures. The sensors could be used in brick, block, stone, and concrete and they could be mounted on the surface or embedded in the materials. There are many research studies on strain gauge devices in structural monitoring; Thick Film (TF) piezo-resistive sensors are proposed as a direct alternative to the widely used metal Foil Strain Gauges (FSG). Due to the low cost of TF sensors, their ease of use, suitability to integrate electronics on board, and to have different geometrical shapes, they could be deployed at different locations in a building, road or be distributed in arrays. This offers the continuous monitoring of stresses at any time by using a data logger on two points on the surface or by using wireless electronic transmission. In this research, new thick film screen-printed ceramic piezo-resistive sensor has been developed and characterized as discrete device for deployment on surface of a structure and embedded into the structure during building material curing or after structure erection. The sensor response on different building materials has been experimented and compared. Mechanical and electronic simulation tools were used to characterise the sensor and to choose an adequate interface electronic circuit. The experimental results of the simulated sensor and circuitry, showed the suitability of the sensor to be embedded in building materials during curing period and on erected structures. Materials used were wood, concrete, brick and plaster. In addition, the overall linearity of response of the sensors applied on building material surface was asserted which makes the technology a candidate for a more wide deployment in SHM field.

APA, Harvard, Vancouver, ISO, and other styles

43

Muckley, Eric S. "Optimization of film morphology for the performance of organic thin film solar cells." Thesis, California State University, Long Beach, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1523341.

Full text

Abstract:

The power conversion efficiency of organic thin film solar cells must be improved before they can become commercially competitive alternatives to silicon-based photovoltaics. Exciton diffusion and charge carrier migration in organic films are strongly influenced by film morphology, which can be controlled by the substrate temperature during film growth. Zinc-phthalocyaninelbuckminsterfullerene bilayer film devices are fabricated with substrate temperatures between 25°C and 224°C and their solar cell performance is investigated here. The device open-circuit voltage, efficiency, and fill factor all exhibit peaks when films are grown at temperatures between 160°C and 180°C, which is likely a result of both the increase in shunt resistance and reduction in undesirable back diode effects which occur between l00°C and 180°C. The device performance can also be attributed to changes in the film crystallite size, roughness, and abundance of pinholes, as well as the occurrence of crystalline phase transitions which occur in both zinc-phthalocyanine and buckminsterfullerene between 150°C and 200°C. The unusually high open-circuit voltage (1.2 V), low short-circuit current density (0.03 mA/cm²), and low device efficiency (0.04%) reported here are reminiscent of single layer phthalocyanine-based Schottky solar cells, which suggests that pinholes in bilayer film devices can effectively lead to the formation of Schottky diodes.

APA, Harvard, Vancouver, ISO, and other styles

44

Zheng, Yulan. "Characterisation and development of novel thick film strain gauges." Thesis, University of Southampton, 2003. https://eprints.soton.ac.uk/47490/.

Full text

Abstract:

The strain gauge is a physical sensor, in which the influence of an externally applied strain causes the resistance to undergo a reversible change. It can be applied to the measurement of force, pressure, and displacement etc. The thick film strain gauge is relatively new however and has been seen to have many advantages. System zero (offset) and system gain (sensitivity) are key characteristics of the strain gauges. Hence intensive research was carried out to study these two aspects of different construction types of thick film strain gauges, i.e. X-plane and Z-plane strain gauges. Different fabrication parameters of these devices were studied for their effect on the characteristic. Temperature characteristics of both of these types of devices were examined as a measure of system zero stability. Combinations of resistor thickness, construction materials and geometric parameters of these types of devices were noticed to affect their temperature behavior. These observations would undoubtedly facilitate the achievement of good TCR matching between resistors in practical application. A programme of explanatory theory to understand these observations has been submitted, which comprises strain analysis and conduction mechanism study. Loading characteristics of Z-plane strain gauges have also been studied to explore the potential of this type of device.

APA, Harvard, Vancouver, ISO, and other styles

45

Mihell, John Alexander. "Ruthenium dioxide thick film pH electrodes." Thesis, University of Southampton, 1997. https://eprints.soton.ac.uk/47133/.

Full text

Abstract:

PH sensitive electrodes have been fabricated using thick film screen printing techniques. Powdered ruthenium dioxide hydrate was incorporated in a printable paste by mixing with an uncured polymer precursor. This paste was printed onto alumina tiles which had been previously patterned with conductive tracking which enabled connection to measurement circuitry. The liquid polymer was cured to a resistant solid using either temperature or ultraviolet light treatments. Large numbers of electrodes were fabricated in this way, using ruthenium dioxide with varying levels of hydration. Printed electrodes were tested for pH response using a number of fixed pH buffers. A commercial silver/silver chloride reference electrode was used to complete the potentiometric measurement cell. The response of electrodes was found to be comparable to that of commercial electrodes based upon a pH sensitive glass bulb. Electrodes were tested after prolonged soaking in various solutions, both acidic and alkali. Some types of printed electrode showed signs of chemical attack and failure after storage in acidic media. Charge was passed through electrodes to investigate the possible perturbation of electrochemical equilibria within the oxide. Electrodes were characterised by microscope examination of used and unused samples. The hydration level of the oxide powders used was investigated using thermogravimetric analysis techniques. The electrochemical mechanisms underlying the potentiometric pH response are speculated upon. The experimental evidence could indicate that an ion exchange mechanism involving hydroxide groups on the oxide surface is responsible for pH sensitivity. Results are discussed with respect to this and other mechanisms.

APA, Harvard, Vancouver, ISO, and other styles

46

Yang, Guoning. "Essays on firm heterogeneities, click-through fees and pricing in oligopoly theory and estimation /." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3319890.

Full text

Abstract:

Thesis (Ph.D.)--Indiana University, Dept. of Economics, 2008.
Title from PDF t.p. (viewed on May 11, 2009). Source: Dissertation Abstracts International, Volume: 69-08, Section: A, page: 3253. Advisers: Michael Baye; Michael Rauh.

APA, Harvard, Vancouver, ISO, and other styles

47

Lopez, Lira Arjona Alfonso. "Inter-firm knowledge transfer and experiential learning| A business sustainability approach on SME's absorptive capacity." Thesis, Instituto Tecnologico y de Estudios Superiores de Monterrey (Mexico), 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3570884.

Full text

Abstract:

In emerging economies, Small and Medium-Sized Enterprises (SMEs) are threatened by continuous political and economic changes. In such uncertain environments, knowledge is the distinctive factor for the achievement of a competitive advantage. However, limited funds and pressure from competitors force SMEs to seek for external sources of knowledge.

The Multinational Corporation (MNC) represents an alternative for business sustainability within the value chain, including both suppliers and clients. In the aim for pursuing such endeavor, a conceptual framework including inter-firm knowledge transfer processes from the MNC and experiential learning enhanced by the Academia is explored.

In sum, this dissertation is intended to examine the MNC’s and Academia’s role on the procurement of SMEs’ business sustainability through inter-firm knowledge transfer and experiential learning, in terms of absorptive capacity. More specifically, the impact of technical and technological knowledge transferred from the MNC on one side; and reflective learning on managerial skills and business vision from the Academia on the other side, is analyzed through SMEs’ absorptive capacity. Regarding business sustainability, the effect of the application of newly absorbed knowledge is analyzed in terms of SMEs’ selected indicators for business improvements. As a complement, a qualitative study is included in order to provide support for findings hereby obtained.

APA, Harvard, Vancouver, ISO, and other styles

48

Silieti, Mahmood. "INVERSE BOUNDARY ELEMENT/GENETIC ALGORITHM METHOD FOR RECONSTRUCTION O." Doctoral diss., University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3325.

Full text

Abstract:

A methodology is formulated for the solution of the inverse problem concerned with the reconstruction of multi-dimensional heat fluxes for film cooling applications. The motivation for this study is the characterization of complex thermal conditions in industrial applications such as those encountered in film cooled turbomachinery components. The heat conduction problem in the metal endwall/shroud is solved using the boundary element method (bem), and the inverse problem is solved using a genetic algorithm (ga). Thermal conditions are overspecified at exposed surfaces amenable to measurement, while the temperature and surface heat flux distributions are unknown at the film cooling hole/slot walls. The latter are determined in an iterative process by developing two approaches. The first approach, developed for 2d applications, solves an inverse problem whose objective is to adjust the film cooling hole/slot wall temperatures and heat fluxes until the temperature and heat flux at the measurement surfaces are matched in an overall heat conduction solution. The second approach, developed for 2d and 3d applications, is to distribute a set of singularities (sinks) at the vicinity of the cooling slots/holes surface inside a fictitious extension of the physical domain or along cooling hole centerline with a given initial strength distribution. The inverse problem iteratively alters the strength distribution of the singularities (sinks) until the measuring surfaces heat fluxes are matched. The heat flux distributions are determined in a post-processing stage after the inverse problem is solved. The second approach provides a tremendous advantage in solving the inverse problem, particularly in 3d applications, and it is recommended as the method of choice for this class of problems. It can be noted that the ga reconstructed heat flux distributions are robust, yielding accurate results to both exact and error-laden inputs. In all cases in this study, results from experiments are simulated using a full conjugate heat transfer (cht) finite volume models which incorporate the interactions of the external convection in the hot turbulent gas, internal convection within the cooling plena, and the heat conduction in the metal endwall/shroud region. Extensive numerical investigations are undertaken to demonstrate the significant importance of conjugate heat transfer in film cooling applications and to identify the implications of various turbulence models in the prediction of accurate and more realistic surface temperatures and heat fluxes in the cht simulations. These, in turn, are used to provide numerical inputs to the inverse problem. Single and multiple cooling slots, cylindrical cooling holes, and fan-shaped cooling holes are considered in this study. The turbulence closure is modeled using several two-equation approach, the four-equation turbulence model, as well as five and seven moment reynolds stress models. The predicted results, by the different turbulence models, for the cases of adiabatic and conjugate models, are compared to experimental data reported in the open literature. Results show the significant effects of conjugate heat transfer on the temperature field in the film cooling hole region, and the additional heating up of the cooling jet itself. Moreover, results from the detailed numerical studies presented in this study validate the inverse problem approaches and reveal good agreement between the bem/ga reconstructed heat fluxes and the cht simulated heat fluxes along the inaccessible cooling slot/hole walls
Ph.D.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Mechanical Engineering

APA, Harvard, Vancouver, ISO, and other styles

49

Siew, Chan-Cheong. "On the non-linear vibration of rotor-squeeze film damper assemblies." Thesis, University of Southampton, 2001. https://eprints.soton.ac.uk/47560/.

Full text

Abstract:

Squeeze film dampers (SFDs) have long been used to attenuate the vibration of high-speed rotating machines such as gas turbine engines, turbo-chargers, etc. Due to their highly non-linear behaviour, it is often difficult to calculate the steady state vibration response of rotor-SFD systems. Over the years, methods such as the Runge-Kutta-Merson Method (RKMM) have been applied to solve the non-linear equations of motion for the system. However such a method requires huge amounts of computational time especially when a flexible shaft system is involved. In order to accelerate the calculations of the rotor-SFD system vibration response, the Modified Harmonic Balance Method and the Modified Iteration Method are introduced in this work. It is shown that their results agree very well with the RKMM predictions and the experimental measurements. The circumferential oil-feeding groove within the SFD radial clearance is designed to prevent oil starvation in the squeeze film. The pressure generated by the groove is traditionally neglected. To date, many experiments are designed to test SFDs with groove-depth to clearance ratios (cg/c) between 3 to 10 but no attempts have been made to assess the merits and weaknesses of various existing squeeze film force models under a wider range of parameters. In this work, the vibration responses of the SFDs tested with various groove depths (i.e. 340). These observations should be sufficient to provide useful guidelines for engineers to design a shallow or deep grooved SFD-rotor assembly. The SFD can be sealed to increase its damping. Empirical methods are commonly used to predict the vibration response but deeper understanding of the oil flow within the damper is not achieved. In this work, the flow balance principle is used to find the boundary conditions of the end-sealed SFD. With the assumption of a short bearing, averaging the one-land and two-land pressure distributions within the damper clearance, the current research shows that a good estimation of the end-sealed SFD vibration can be achieved. Such a model would be useful for the development of a comprehensive analytical end-sealed SFD model.

APA, Harvard, Vancouver, ISO, and other styles

50

Holt, Kristine M. "Through fire and ice| The olympic cauldron park carves a legacy." Thesis, The University of Utah, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1550645.

Full text

Abstract:

In 2002, Salt Lake City joined an elite group of cities, in the world, when it hosted the 2002 Olympic Winter Games. This "once in a lifetime" chance gave the city, community, and state of Utah an opportunity to show the world a different side of the community than just the home to the peculiar people known as Mormons. The city took the chance and pulled it off beautifully. Salt Lake not only managed to stage one of the most impressive Olympic Winter Games ever but ended up with an unprecedented amount of profit. But what do you do after the party is over? In an effort to keep the spirit of the Olympics alive, the Salt Lake Organizing Committee (SLOC) wanted to build a legacy park where locals and tourists could visit and relive the thrill and excitement the Olympics. The announcement of the legacy park brought great support from the people, the city, and state government officials but unfortunately, it also brought along all of the politics and personal agendas involved when working with these entities. In the end, the legacy park was merged with a park which was originally planned to showcase just the Olympic cauldron at Rice-Eccles Stadium at the University of Utah. The following thesis is the story of how the legacy park came to reside at the University of Utah, the planning and design of the park, the operations and maintenance, and the celebrations it hosted in the ten plus years since the Olympic Winter Games. This thesis focuses on whether or not the Olympic Cauldron Park served as a legitimate and appropriate legacy for the 2002 Salt Lake Olympic Winter Games and if that legacy should continue now that original contracts are expiring. Primary research was gathered through local and national newspaper articles, oral interviews, personal experience, and official documents such as contracts between SLOC and the University of Utah. As time and the outdoor elements take their toll on the park, contracts are finished and expansion of the stadium for the Pac 12 Athletic Conference pending, the future of the Olympic Cauldron Park looks bleak. Although there are plans to have some items from the park live on at another Olympic legacy destination, the Olympic Cauldron Park story needed to be told before it ceases to exist.

APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic 'Generic firm'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles