This dissertation contains a number of varied, yet closely related, results that are relevant to the construction of mathematical and statistical models of inventory systems. Its primary focus is on the sensitivity of some specific inventory models to errors in certain modeling assumptions. Motivation for this research is provided through the development of analytical expressions that show that the deterministic economic order quantity can be quite sensitive to errors in the forecast of the demand rate whenever the lead time is non-zero. Similar results are provided for the stochastic case by means of a carefully designed experiment that shows that the specific form or "shape" of the distribution chosen to represent the stochastic behavior of the lead time demand can have a significant impact on a minimum cost (Q,R) policy. Together, these results refute the "conventional wisdom" that inventory models are generally insensitive to errors in model specification or parameter estimation. Considerable attention is also given to the postulation of a "robust" model for the lead time demand distribution (LTDD). This discussion culminates with the introduction of a new probability distribution, based on a hyperbolic cosine transformation of normal random variables, that appears to be well-suited for modeling the LTDD. Furthermore, it is concluded that the two- and three-parameter versions of the lognormal and inverse Gaussian distributions can also be considered as viable candidates to model the LTDD in a wide variety of inventory systems. A number of new algorithms for computing optimal (Q,R) policies are also introduced. These significantly reduce both the amount and complexity of computation required by the standard iterative method. Two additional sets of analytical results are chronicled in this work. The first allows the LTDD to be characterized (by its first four moments) on the basis of information about the distributions of the lead time and demand rate. The second expresses the linear loss functions (LLF's) for a number of probability distributions whose LLF's are not readily available in the inventory control literature. Complete and intuitive proofs of these results are included.

Seasonality is a common phenomenon in the tourism industry around the world. Húsavík, a town on the northern coast of Iceland, has experienced tremendous growth in tourism in recent years and is sometimes recognised as the „Whale Watching Capital of Europe‟. However, Húsavík faces extreme seasonality with high demand mainly during the summer months and limited or no demand at other times of the year. As is emphasised in the tourism literature and widely in practice, seasonality is frequently seen as a problem for the tourism industry which has to be tackled. Academic research has never before been done on seasonality in Húsavík and the aim of this thesis is to understand the nature of seasonality within the tourism industry in Húsavík and discover potential ways to reduce seasonality in Húsavík tourism. In order to fulfil the aim, qualitative semi-structured interviews were undertaken with six tourism managers in Húsavík to investigate their perceptions of seasonality and if and how it could be managed. The results confirmed that the peripheral location of the destination stimulates seasonality and it poses major economic challenges for tourism businesses in Húsavík. Managers would prefer a longer tourism season. Several recommendations were provided for how to reduce seasonality such as develop other attractions than whale watching, improve accessibility, focus marketing on seasons outside the summer, and offer winter packages for foreign and domestic tourists.

Globally, the tourism industry is recognised as one of the fastest growing industries, generating high revenues and creating a vast number of job opportunities. In South Africa, this is no different and, in recent years, the tourism industry has outshone the country's gold exports therefore claiming its position as the fourth highest earner of foreign exchange to date. Yet the industry is still to receive the attention it deserves from conventional economics. This research aimed to fill this gap in South Africa by providing an understanding on the determinants of international tourism demand for South Africa. The first objective of the study was to provide a broad overview of the tourism industry of South Africa. The discussion focused on the supply and demand sides of tourism which, in turn, are divided into the domestic and international tourism markets. There has been a high growth, especially in the international market since 1994 and, while domestic and international markets continue to grow, seasonality remains an issue. Tourism has a significant impact on economic activity, employment, and the balance of payments and therefore the industry has great potential. The second objective was to create a theoretical understanding on the different factors that could determine the international demand for the tourism product. From this discussion it was found that there are various economic and non-economic factors that are believed to have an influence on tourism demand. Income, prices, transport cost, and the exchange rate are amongst the favourite economic variables with travel time, population, marketing expenditure, climate, and capacity being the more popular noneconomic factors. Among these, certain threats were also identified that could have harmful impacts on tourism growth. The third objective and main aim of the study was to determine which of the factors identified earlier determine the demand for international tourism to South Africa. This was done through an empirical investigation. Data from all the continents were used to attain an international perspective on tourist arrivals (tourism demand). The results indicated that capacity and climate factors determine tourism demand in the short term with income and transport cost influencing South Africa as a tourism destination in the long term. The last objective was to determine whether certain events or disasters that take place globally have a negative influence on tourism demand to South Africa. The event that was looked as was the terror attacks on the United States in September 2001. It was found that although the overall tourism activity of the world became stagnant during this period, the effect was not that considerable in South Africa's tourism arrivals. Tourism in countries such as the United Sates, on the other hand, has still not recovered fully after this event. / Thesis (M.Com. (International Commerce))--North-West University, Potchefstroom Campus, 2007.

The thesis investigates the application of ice thermal storage technology to situations where the price of electricity varies continuously with instantaneous network demand. A central hypothesis is postulated in chapter 1, which states: "A variable electricity pricing structure, in which unit price continuously varies in response to instantaneous network demand, enhances the opportunities and benefits of ice thermal storage. The benefits both financial and environmental are dependent on the establishment of control and design strategies which optimise performance by matching refrigeration load with the instantaneous electricity price. " For ease of reference, the form of pricing described above is referred to in the thesis as 'real time' electricity pricing. The 'pool price' which is used to facilitate the competitive electricity awkct in England and Wales, is one of the foremost examples of real time pricing. The thesis therefore uses the electricity supply industry in the UK as its research vehicle. Notwithstanding this, the work contained in the thesis can be applied to any country which applies real time electricity pricing mechanisms. The validity of the hypothesis is assessed in the thesis through the development of a variety of numerical and computer models. These models fall into two distinct categories; those concerned with predicting and optimising the financial benefits of ice thermal storage, and those concerned with predicting and optimising the environmental benefits of ice thermal storage. Chapters 2,3 and 4 should be treated as support chapters, which equip the reader with the prerequisite knowledge necessary to understand the research work contained in the later chapters. As such, these chapters contain, respectively, a description of the electricity supply industry in the UK, a discussion of demand side management in the UK, and a description of the technology involved in ice thermal storage. The parametric study contained in chapter 4 is however an original piece of research work by the author. The models developed to evaluate and optimise the economic benefits of ice thermal storage are presented in chapters 5 and 6, and are applied to contrasting theoretical case study applications, namely an office building and a dairy. In chapter 5a 'long hand' numerical analysis technique is used. In chapter 6 this technique is rationalised and developed into a computer model for optimising both the design and control of ice storage installations in real time electricity pricing applications. The environmental studies are presented in chapter 7. These concentrate on the ability of ice thermal storage to reduce carbon dioxide emissions. Although the overall objective of the chapter is to evaluate the carbon dioxide emissions associated with ice thermal storage, the bulk of the chapter is concerned with the development of a model for predicting the carbon dioxide emissions per kWh of delivered electrical energy in England and Wales on a time related basis. The development of this 'time of day' carbon dioxide model is one of the main objectives of the thesis. Having established this model, it is then used to analyse the carbon dioxide emissions associated with the dairy case study.

This thesis aims to study the macroeconomic performance of China. China has been experiencing rapid economic growth and it has been changing gradually from a planned to a market economy since it initiated the well known “open door policy” combined with a “coastal development strategy” in 1978. However, rapid growth has occurred on the background of increasing regional disparity. Meanwhile, unemployment has increased significantly during last two decades, and has become one of the most pressing problems of the Chinese economy today. Moreover, another major challenge facing the Chinese economy is how to deal with various shocks, and to ensure the sustainability and balance of economic growth in the face of the increasing economic uncertainties associated with its deep reform and integration into the world trade and financial system. Based on the above concerns and literature review, this study, firstly, uses an augmented Solow-Swan model of Mankiw, Romer and Weil (1992) to assess the role FDI plays in underlying regional differences in economic growth across Chinese provinces over the reform period 1978-2008. My analysis indicates that the augmented Solow growth model appears to provide a good description of regional growth patterns in China over the period 1978-2008 and the data display conditional convergence. After controlling for FDI and other determinants of growth, provinces that were initially poor tend to grow faster and the evidence in favour of conditional convergence becomes even stronger after splitting the data into subsamples. I then focus on the study of the relationship between unemployment and growth at both national level and regional level in order to find out how unemployment affects China’s economic growth and economic reform progress overall. I find that Okun’s relationship does not hold in China universally and, furthermore, the nature of the observed relationship has changed during the transition progress. I argue that there are hump shaped relationships both between growth and unemployment and between the speed of transition and unemployment in China. The results are consistent with several theoretical and empirical studies in the literature. Finally, structural VAR methodology pioneered by Bayoumi and Eichengreen (1993) is used to identify and decompose supply and demand shocks to two variables, (the log of) output (annual real GDP) and (the log of) prices (annual GDP deflator). I then compute and discuss the correlation of such shocks across provinces and show how it has evolved over the four main sub-periods of China’s history. Moreover, I investigate which factors contribute to economic integration or divergence in the Chinese economy.

The politics of the act is an important part of radical politics as it seeks to disrupt and challenge the status quo. I define the politics of the act as a mode of politics that involves a withdrawal from the state, mobilises around non-hierarchical organising structures and is animated by an imperative of enactment. This can be contrasted with a politics of demand, which is state-oriented, hierarchical in nature and looks to educate the movement for enactment. While Marxists have tended to privilege the politics of demand as the route to radical change, anarchists have favoured the politics of the act, thus creating a clear opposition between these two different ways of acting politically. In this thesis I will argue that this dichotomy between a politics of demand and a politics of the act is overemphasized, and using Deleuze I will show that a politics of the act is the ontological and creative basis through which the politics of demand comes into being, and the politics of demand is enacted by capturing certain flows of creativity into recognisable ‘moments’ that allows them to be made visible and understood at a societal level. Thus, these modes of politics, although they have meaningful differences, are not distinct from each other but rather flow into each other. In IR, conceptualisations of social movements practising a politics of demand have overshadowed the politics of the act, although anarchists have recognised its importance. This thesis will build on this work by drawing on Deleuzian concepts to deepen our understanding of the politics of the act both conceptually and empirically and contributing to the development of a postanarchist politics. It will examine six case studies of activities that are valorised as exemplifying the politics of the act: withdrawal from the state by Food Not Bombs and Social Centres; horizontal organising structures of Critical Mass and Indy Media Centres; and an imperative of enactment through guerrilla gardening and the Clown Army. This thesis challenges those conceptualisations of politics that privilege either the politics of demand or the politics of the act, and demonstrates that both are needed in any conceptualisation of radical politics. It concludes by offering a way of conceptualising both modes of politics through a ‘politics of the molecular’.

The United States is the leading producer and exporter of corn and soybeans in the world. The United States exports 20% of the world’s corn and 30% of soybeans in a typical year (USDA, ERS). The U.S., being the top producer and exporter of these commodities, is also confronting major rivals such as Argentina, Brazil, and Ukraine, which are increasing their exports and causing the U.S. to lose some of its market share. In order to stop this decline in market share, the U.S. can adopt and implement different policies to manage resources and employ advanced technology more effectively. In this study, we empirically estimate the export demand function of U.S. corn and soybeans to the top four export destinations: China, Japan, European Union, and Mexico in the current context of energy and agriculture linkages and production of ethanol from corn. A log-linear, panel data equation is used to estimate the U.S. corn and soybeans export demand function. Own price, cross price, income and exchange rate elasticities are estimated econometrically. Data for the U.S. and its top four importer countries were gathered for the 1980-2012 period. A Hausman test implies that a random effects estimator is better for the estimations. Elasticity analysis indicates that U.S. corn demand is elastic to own price, cross price, income and poultry inventory, while inelastic to real exchange rate and pig inventory. The positive cross price elasticity reveals that corn and soybeans are substitutes in these countries. Conversely elasticity analysis for the U.S. soybean demand shows elastic cross price, real exchange rate, and pig and poultry inventory effects, while inelastic own price and income effects. Consequently, for the U.S. to gain more international market share, U.S. corn and soybean producers need to take advantage of their advanced technology and high management skills to increase quality and have more competitive pricing compared to rivals. The U.S. can gain more market share by employing better regulation to increase the quality of products, and provide incentives to U.S. farmers and exporters that could help boost their advantages in a highly competitive international environment. Higher quality and more product differentiation could help in this regard. This could help U.S. farmers increase exports to currently existing foreign destinations and access new markets, to expand market shares.

Denna studie utvärderar ekonomiska styrmedels effekt på konsumtionen av livsmedel samt ifall skatter och subventioner kan vara en metod som styr matkonsumtionen mot hälsosamma livsmedelsval. Sex livsmedelsgrupper analyseras i studien och dessa är sötsaker och glass, kött, grönsaker, mejerivaror, bröd och spannmålsprodukter samt frukt och bär. Fyra scenarier som representerar olika skatte- och/eller subventionsreformer simuleras för att analysera vilken effekt ekonomiska styrmedel kan ha på matkonsumtion och hälsa. Responsen som de ekonomiska styrmedlen har på matkonsumtionen beräknas med elasticiteter som tagits fram från parameterestimat i AIDS-modellen. Den data som ligger till grund för den ekonometriska modellen är aggregerad konsumtionsdata, konsumentprisindex och livsmedelsförsäljning. Resultatet från studien visar att det går att styra konsumtionen av livsmedel men att substitution mellan varor kan leda till att de hälsomål som reformen är menad att nå inte uppfylls.

The concept of CSR is increasingly important in society, and firms are expected to be profitable while ethical. Deciding how to best engage in CSR activities can be difficult, but using a supply-and-demand framework can help firms to maximize their CSR activities. However, the demand for CSR has been proven difficult to measure, but can perhaps be established when dividing the demand into different components. The purpose of this study is therefore to investigate how consumer awareness, attitude, and buying behavior, in relation to CSR, affect each other; to establish a measurement for consumer demand for CSR. To find an answer, an explanatory and a deductive research approach was used and consumers were surveyed in a quantitative study to establish a measurement for the consumer demand for CSR. This study provides both managerial and theoretical implications to the field of CSR. The theoretical implication lies in contributing empirical evidence into the discussion of supply-and-demand for CSR. Practically, this study informs managers, in the fast fashion industry, that consumer attitude can be used as a measurement when establishing the consumer demand for CSR. It is suggested for future research that it would be interesting to use other control variables to further elaborate on the findings of this study.

Losing ownership and control over the development of and connection to our own person detaches us from the most innate embodiment of ourselves, our person. Without being able to develop and connect to our person, we become detached from expressing our identity, exercising our autonomy, and formulating our own values, the most intrinsic features our person encapsulates. While we yearn to act on our own projects to express our identity, exercise our autonomy, and formulate our own values the way we want, morality imposes huge demands on our person that restrain us from doing so. Morality’s major requirement to always act on morally significant projects to produce the overall good puts us at risk of forfeiting our identity, autonomy, and values. Despite these features being the most innate embodiment of ourselves, morality neglects them so that we always participate in its domain of beneficence to further the interests of others who are in need. Even though great benefits result from always acting on morally significant projects to produce the overall good, we are at odds with moral beneficence because of the demands it imposes on our person. In this thesis, it is argued what makes a moral theory too demanding. Arguments by Bernard Williams, Samuel Scheffler, Liam B. Murphy, and Richard W. Miller are evaluated to construct views of what makes a moral theory too demanding for them. Afterwards, differences and commonalities are drawn from their views to frame the final view of what makes a moral theory too demanding that is argued here. All of the philosophers’ views contribute to the claim that we are entitled to our lives outside of morality’s domain of beneficence. Afterwards, it is explained why we are entitled to our lives outside of morality’s domain of beneficence. The most compelling explanation is that the potential development of our own person entitles us to do so outside of morality’s domain of beneficence. By developing our person to its fullest height on our own terms and conditions, we can connect to it in the best way possible. Nonetheless, because we are forced to always participate in morality’s domain of beneficence, we lack the ownership and control over the development of and connection to our own person. The demandingness of morality holds the reins over this relation between the development of and connection to our person when in fact we should.