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<p dir="ltr">The next generation of sustainable (alternative) aviation fuels (SAFs) must abide for simplified chemical compositions that will provide higher gravimetric and volumetric energies with a minimum aromatic content. The use of ethanol in the U.S represents a marvelous technical and economic opportunity to synthesize jet fuel range compounds, especially cycloalkanes, via an alcohol-to-jet (ATJ) process using alkenes (olefins) intermediates by employing existing infrastructure. Cycloalkanes stand out as promising compounds with the potential to achieve higher gravimetric and volumetric energy contents while still meeting fuel drop-in requirements, including the ability to swell O-rings. In this project, the influence of blending target cycloalkanes into Jet A on the energy content, density, and viscosity of Jet A was systematically explored (<i>Chapter 3</i>). Different alkyl-chain lengths, position of substituents, heavy atom connectivities (isomeric structures), molecular geometries, and number of rings provided key technical information to facilitate the control of the physical properties of jet fuels based on addition of cycloalkanes. Complementary, the kinematic viscosity of conventional jet fuels and alternative blending components at -20 °C was successfully predicted based on their chemical composition via GC×GC/FID by using a partial least squares (PLS) model and a Yeo-Johnson transformation offering lower prediction errors than other methods available in the literature (<i>Chapter 4</i>). Finally, a quantitation method for alkanes, branched alkanes, cycloalkanes, and alkenes was proposed by using GC×GC/(+)EI-TOF-MS data only (<i>Chapter 5</i>). This method uses experimental correction factors for the chromatographic peak area for each group of compounds based on their hydrocarbon group, number of carbon atoms, and degree of branching as factors influencing their different ionization efficiencies. This information broadens the understanding of missing factors in the ATJ process by providing insights regarding the role of cycloalkanes in alternative jet fuel formulations, improving the prediction capabilities to estimate the kinematic viscosity of jet fuels and alternative fuel blending components at low temperatures, and helping to facilitate the chemical characterization and quantitation of complex mixtures of hydrocarbons, including alkenes (olefins), without using GC×GC/FID or expensive model compounds.</p>

本論文分為兩部分，第一部份是探討全球航空產業的油料避險會不會對公司價值有所影響，以及油料避險的誘因。第二部份則是檢視全球航空公司的風險曝露會不會影響分析師的預測誤差，尤其是燃油價格變動的風險曝露。 / In the first essay, we examine whether jet fuel hedging increases the market value of airline companies around the world. Using a sample of 70 airline companies from 32 countries over the period 1995 to 2005, we find that jet fuel hedging is not significantly positively related to their firm value in the global airlines, but this positive relationship holds in the various sub-samples and is significant for US and non-alliance firms. Moreover, our results show that the risk-taking behavior of executives and the tendency to avoid financial distress are important determinants for the jet fuel hedging activities of non-US airline companies. Alleviating the problem of underinvestment is also an important factor to explain the jet fuel hedging activities of US and non-alliance firms. Our results add support to the growing body of literature which finds that hedging increases firm value for global airline companies. In the second essay, we examine the extent analysts revise their earnings forecasts in response to oil price, interest rate and foreign exchange rate shocks they have observed during the year, and whether these revisions contain additional information about how current and past price shocks affect reported earnings, using the sample of the global airline industry. Empirical results indicate that jet fuel hedging can increase analysts’ forecast revisions in the total sample, and in the sub-sample of the volatile fuel price period. These results can also be seen in US and non-US airlines, and airlines with both strong and weak governance. Overall, our results show that oil price shocks play an important role in investor and analyst information uncertainty with regard to the global airline industry. Consequently, corporate risk disclosures only provide limited information about firms’ financial risk exposures. Two essays are comprised in this dussertation to examine whether jet fuel hedging has effects on firm value and analysts’ forecast accuracy in the global airline industry. Using global data allows us to cmpare the differences of jet fuel hedging behavior and incentives for hedging across different sub-samples. Furthermore, we also examine how jet fuel hedging affects analysts’ forecast erros across different sub-samples and its implications for firm disclosures about their risk exposures in the financial reports. In the first essay, we examine whether jet fuel hedging increases the market value of airline companies around the world. Using a sample of 70 airline companies from 32 countries over the period 1995 to 2005, we find that jet fuel hedging is not significantly positively related to their firm value in the global airlines, but this positive relationship holds in the various sub-samples and is significant for US and non-alliance firms. Moreover, our results show that the risk-taking behavior of executives and the tendency to avoid financial distress are important determinants for the jet fuel hedging activities of non-US airline companies. Alleviating the problem of underinvestment is also an important factor to explain the jet fuel hedging activities of US and non-alliance firms. Our results add support to the growing body of literature which finds that hedging increases firm value for global airline companies. In the second essay, we examine the extent analysts revise their earnings forecasts in response to oil price, interest rate and foreign exchange rate shocks they have observed during the year, and whether these revisions contain additional information about how current and past price shocks affect reported earnings, using the sample of the global airline industry. Empirical results indicate that jet fuel hedging can increase analysts’ forecast revisions in the total sample, and in the sub-sample of the volatile fuel price period. These results can also be seen in US and non-US airlines, and airlines with both strong and weak governance. Overall, our results show that oil price shocks play an important role in investor and analyst information uncertainty with regard to the global airline industry. Consequently, corporate risk disclosures only provide limited information about firms’ financial risk exposures.

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