Arguments from underdetermination take two forms, those from global sceptical underdetermination, global scientific underdetermination and local underdetermination. Arguments from global sceptical underdetermination bring into question all knowledge, they develop sceptical scenarios that purport to show that we cannot trust any knowledge that we obtain within the world. Arguments from local underdetermination aim to bring into question the nature of our knowledge and are geared against scientific realism. This thesis is an evaluation of the arguments that claim to do the latter, however it shows that these arguments are not arguments from local underdetermination but are from a type of global underdetermination that I call global scientific underdetermination. Based on this evaluation a new argument from local underdetermination is developed that attempts to show that nevertheless local underdetermination is indeed a problem for scientific realism. However, I argue that this argument also fails to undermine scientific realism. Recently Kyle Stanford has reintroduced an historical argument from underdetermination that he calls the argument from unconceived alternatives. Stanfords argument from unconceived alternatives is an inductive historical argument. It maintains that scientific theories are chosen from a non-exhaustive set of theories; claiming there is always at least one unconceived alternative that would better explain the empirical evidence. Stanfords new induction attempts to undermine scientific realism by arguing that our most successful theories will eventually be shown to be false. Various arguments against this induction will be considered. It will be shown that traditional scientific realism fails to address the argument from unconceived alternatives and the only form of scientific realism that can overcome this problem is structural realism.

The thesis is aimed to propose a financial innovation called COCONUT payment system. This innovative payment system is based on a combination of the cash and electronic money, presented as an ATM-like machine for purchase and payment execution, and operated via an electronic account, which allows its users to operate as a credit cards owner. This study commences with a review of the current major payment systems in the United States, followed by an analysis of the strength and weakness of these systems, and then proposes a payment system that combines the most popular two: cash and credit card with a healthier mechanism on financial control to both avoid the recurrence of financial crisis caused by credit crush and keep the current benefits. The COCOCNUT system can be applied not onbly to the market of the USA, but BRIC, developing and under seveloped countries’ market, those regions where cash remains the major payment way. As for the feasibility and the probability of promoting and applying this new system to replace the current systems or to implement in the new markets, the proposed COCONUT payment system, takes into consideration the differences of markets and regional regulations. The COCONUT project also provides trial calculations of its value proposition from the perspective of the project realization.

El sector energético se está dirigiendo hacia un nuevo paradigma, favoreciendo la aparición de procesos de conversión más eficientes, el uso de las fuentes de energía renovables y la micro-generación. La bioenergía es una solución prometedora para la futura combinación de energías. Los conceptos de ingeniería deben de integrarse junto con los aspectos económicos, ambientales y sociales en el desarrollo de proyectos. Los sistemas de energía centralizados y distribuidos necesitan enfoques a medida para explotar las características de cada posible sistema. Esta tesis investiga el potencial del sector bioenergético, mediante el estudio de la gasificación de biomasa a través de técnicas avanzadas de modelización de procesos y de la incorporación de la gestión de la cadena de suministro, en el marco del diseño conceptual para la toma de decisiones. Los sistemas estudiados son: (i) gasificación integrada con ciclo combinado y con métodos de captura y almacenamiento de CO2 (IGCC-CCS, 285 MWe) para los sistemas de energía centralizados, y (ii) un gasificador de biomasa combinada con un motor de gas (BG-GE, 14 kWe) para los sistemas de energía distribuidos. La superestructura concebida puede ser utilizada en el diseño preliminar de alternativas para los diferentes procesos considerados, para adaptar los ya existentes y para adquirir conocimiento sobre las condiciones de operación de plantas de gasificación. El problema de optimización multi-objetivo considerado evalúa el equilibrio entre los criterios técnico-económicos y ambientales de 25 escenarios, con mezclas de diferentes materias primas y cambios topológicos: mezclas de carbón, coque y biomasa y la generación de electricidad a partir de gas de síntesis, la generación de electricidad a partir de H2 y la producción de H2 puro, considerando o no el uso del gas de purga del PSA en el ciclo combinado. El análisis de Pareto revela que como mejores escenarios el que utiliza coque de petróleo como materia prima para producir H2, con reciclo del gas de purga del PSA y el que utiliza biomasa residual sin reaprovechamiento del gas de purga del PSA. La implementación de la tecnología CCS conlleva una penalización en la eficiencia de un 8,7% en términos de potencia neta, si el H2 se utiliza en el ciclo combinado. La gestión de cadenas de suministro de sistemas centralizados, señalan que España tiene potencial de biomasa residual, invirtiendo en nuevas centrales IGCC-CCS, o para producir electricidad mediante co-combustión en las centrales térmicas de carbón ya existentes. Para el primer caso, el valor actual neto óptimo es 230 millones de € para un periodo considerado de 25 años. Para el segundo caso, se ha calculado que las políticas de subvención en este tipo de proyectos deben de tener en cuenta la sostenibilidad económica, cubriendo en un rango de 5,84% a 20,25% el aumento de los precios de la electricidad. El caso de estudio propuesto y optimizado como ejemplo de un sistema distribuido tiene en cuenta una comunidad de Ghana en el marco de la electrificación rural, a abastecer con peladuras de yuca y mediante sistemas BG-GE. Los resultados revelan una red inviable. De las cadenas de suministro resultantes como óptimas, se puede deducir que cierto nivel de centralización es necesario para que las propuestas sean sostenibles en el tiempo. El sector de la bioenergía cumple ofrece ventajas en términos de impacto ambiental y social. Su implementación es posible con el apoyo de las tecnologías actuales de conversión de energía. Los principales retos están en la mejora de los procesos de pretratamiento de la biomasa y en su almacenamiento. La conversión de la biomasa, junto con los métodos de captura y almacenamiento de CO2, necesitan de incentivos políticos para poder penetrar definitivamente en el mercado, como sería el caso de cualquier otra tecnología alternativa de conversión de energía / The energy sector faces a new energy paradigm, with more efficient conversion processes, renewable sources and micro-generation. Bioenergy is a promising solution. Engineering aspects must be integrated with economic, environmental and social aspects in bioenergy projects. Biomass properties enhancement is crucial. It concerns energy and matter densifications, for stabilisation and easier transport. Tailor-made approaches are needed to account for the characteristics of each potential system, being it centralised or distributed. This thesis has assessed the bioenergy potential using advanced modelling techniques, enlarged with supply chain management strategies, in the framework of conceptual design for decision-making. The studied energy systems are (i) an integrated gasification combined cycle power plant combined with carbon capture and storage (IGCC-CCS, 285 MWe) for centralised energy systems, and (ii) a biomass gasifier with a gas engine (BG-GE, 14 kWe) for distributed energy systems. Process system modelling and optimisation approaches are integrated with supply chain management to analyse co-gasification and co-production of electricity and hydrogen alternatives in IGCC-CCS, and co-combustion of biomass and coal in pulverised coal power plants in the light of economic and environmental considerations. Process modelling is integrated with supply chain management optimisation for rural electrification by BG-GE systems, considering economic, environmental and social issues. The superstructure can be used for the design of process alternatives, retrofit of existing ones and to gain knowledge on operation of IGCC-CCS. The multi-objective optimisation problem evaluates the trade-off between techno-economic and environmental criteria of 25 scenarios. Considerations comprise different coal, petcoke and biomass combinations and electricity generation from syngas, electricity generation from H2 and purified H2 production without and with PSA purge gas use in the combined cycle. The Pareto frontier analyses reveals that the scenario with petcoke as feedstock for H2 production with PSA flue gas profit is the best in terms of techno-economic optimisation. The scenario with residual biomass without PSA flue gas profit is the best in terms of environmental optimisation. CCS technology implementation leads to an efficiency penalty of 8.7% in net power terms if H2 is used in the IGCC. To maintain the same power level than that obtained with the combustion of syngas, the feedstock should be increased by 21% on a mass basis. Supply chain studies highlight, for Spain, a huge biomass waste potential for electricity and H2 production by investing on new IGCC-CCS power plants, or adaptation of existing plants. For the first case, the optimal NPV is around 230M€ for a period of 25 years. The sensitivity of the optimal solutions to changes in prices is demonstrated. For the second case, policy subsidies or alternatively price increases range from 5.84% to 20.25%. The investment is within 549M€ and 1640M€. A supply chain in a specific community from Ghana is proposed for rural electrification using cassava peels. Optimisations considers 9 communities and an overall electricity demand of 118 MWh/yr. The results reveal an unviable network. From the resulting networks, distributed approaches need a certain level of centralisation to be feasible on time. Bioenergy offers decisive advantages in terms of environmental and social impacts. Its deployment is straightforward to support with current energy conversion technologies. Challenges concern the biomass pre-treatment and storage. Despite all the striking advantages, political incentives are needed for definitive market entry, as would be the case for any energy conversion alternative.

External world skeptics argue that we have no knowledge of the external world. Contextualist theories of knowledge attempt to address the skeptical problem by maintaining that arguments for skepticism are effective only in certain contexts in which the standards for knowledge are so high that we cannot reach them. In ordinary contexts, however, the standards for knowledge fall back down to reachable levels and we again are able to have knowledge of the external world. In order to address the objection that contextualists confuse the standards for knowledge with the standards for warranted assertion, Keith DeRose appeals to the knowledge account of warranted assertion to argue that if one is warranted in asserting p, one also knows p. A skeptic, however, can maintain a context-invariant view of the knowledge account of assertion, in which case such an account would not provide my help to contextualism.

Arguments from underdetermination take two forms, those from global sceptical underdetermination, global scientific underdetermination and local underdetermination. Arguments from global sceptical underdetermination bring into question all knowledge, they develop sceptical scenarios that purport to show that we cannot trust any knowledge that we obtain within the world. Arguments from local underdetermination aim to bring into question the nature of our knowledge and are geared against scientific realism. This thesis is an evaluation of the arguments that claim to do the latter, however it shows that these arguments are not arguments from local underdetermination but are from a type of global underdetermination that I call global scientific underdetermination. Based on this evaluation a new argument from local underdetermination is developed that attempts to show that nevertheless local underdetermination is indeed a problem for scientific realism. However, I argue that this argument also fails to undermine scientific realism. Recently Kyle Stanford has reintroduced an historical argument from underdetermination that he calls the argument from unconceived alternatives. Stanfords argument from unconceived alternatives is an inductive historical argument. It maintains that scientific theories are chosen from a non-exhaustive set of theories; claiming there is always at least one unconceived alternative that would better explain the empirical evidence. Stanfords new induction attempts to undermine scientific realism by arguing that our most successful theories will eventually be shown to be false. Various arguments against this induction will be considered. It will be shown that traditional scientific realism fails to address the argument from unconceived alternatives and the only form of scientific realism that can overcome this problem is structural realism.

During the last decades we have seen a growing number of new start-ups in the service/knowledge sector. These types of companies often have no fiscal assets to secure loans with. What types of financing alternatives are there in those situations? I will in this thesis show that there are two directions to choose between to get financial support. By gathering of information I have been able to show that there are more than one alternative to consider when needing funding and that using different alternatives will lead to different results. I will not say which one is the right one, but that there are different ways and there will be different outcomes depending on which one you choose. The study also shows that there are a lot of things you need to take into consideration before using a venture capitalist. An empirical study is made between two companies that decided to use different ways to get the financial support they required. The result shown in this study is that the entrepreneurs own financial situation affect what direction the entrepreneur will take.

The purpose of this study was to gain an understanding of the structure and antecedents of cruise passengers' loyalty. Specifically, the study examined the dimensionality of the loyalty construct. Moreover, the study investigated the utility of applying the Investment Model (Rusbult 1980, 1983) to reveal the psychological processes underlying loyalty formation. The study also attempted to, guided by the Investment Model, integrate the seemingly segregated findings of loyalty antecedents from marketing and leisure/tourism literature. Based on the Investment Model and other marketing and leisure/tourism studies on loyalty, a conceptual framework was established for this study. An online panel survey was conducted to examine this model. Subjects (N = 554) were online panelists who were repeat cruisers and who have cruised at least once in the past 12 months. In this study, loyalty was conceptualized as a four-dimensional construct: cognitive loyalty, affective loyalty, conative loyalty, and behavioral loyalty. Further, the first three components were postulated as three subdimensions of a higher order construct, attitudinal loyalty. However, this conceptualization was not supported by the data. Alternatively, post-hoc analyses revealed that attitudinal loyalty was a first-order one-dimensional construct, containing cognitve, affective, and conative components. Moreover, behavioral loyalty was positively and significantly influenced by attitudinal loyalty. In sum, this study supported the traditional two-dimensional conceptualization of loyalty, which argues that loyalty has an attitudinal and a behavioral component. Following the Investment Model, this dissertation suggested that satisfaction, quality of alternatives, and investment size were three critical antecedents of consumers' attitudinal loyalty. These theoretical relationships were supported by the present study, and collectively, the three predictors accounted for over 74 percent of the variance in attitudinal loyalty. Finally, this dissertation hypothesized that quality and value, two constructs related to loyalty, served as antecedents of satisfaction, with quality also leading to value. Results of the study supported all these hypotheses, and satisfaction was found to partially mediate the quality-attitudinal loyalty, and value-attitudinal loyalty relationships. Results of the present study provide important direction for the development of a holistic theoretical framework to explain the formation and structure of customers' brand loyalty.

In this study we develop a new method for testing the null hypothesis that the predictor function in a canonical link regression model has a prescribed linear form. The class of models, which we will refer to as canonical link regression models, constitutes arguably the most important subclass of generalized linear models and includes several of the most popular generalized linear models. In addition to the primary contribution of this study, we will revisit several other tests in the existing literature. The common feature among the proposed test, as well as the existing tests, is that they are all based on orthogonal series estimators and used to detect departures from a null model. Our proposal for a new lack-of-fit test is inspired by the recent contribution of Hart and is based on a Laplace approximation to the posterior probability of the null hypothesis. Despite having a Bayesian construction, the resulting statistic is implemented in a frequentist fashion. The formulation of the statistic is based on characterizing departures from the predictor function in terms of Fourier coefficients, and subsequent testing that all of these coefficients are 0. The resulting test statistic can be characterized as a weighted sum of exponentiated squared Fourier coefficient estimators, whereas the weights depend on user-specified prior probabilities. The prior probabilities provide the investigator the flexibility to examine specific departures from the prescribed model. Alternatively, the use of noninformative priors produces a new omnibus lack-of-fit statistic. We present a thorough numerical study of the proposed test and the various existing orthogonal series-based tests in the context of the logistic regression model. Simulation studies demonstrate that the test statistics under consideration possess desirable power properties against alternatives that have been identified in the existing literature as being important.

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 162-170).

Η ψηφοφορία είναι ένας δημοφιλής τρόπος για κατανεμημένη λήψη αποφάσεων και παραδοσιακά είναι το αντικείμενο της θεωρίας κοινωνικής επιλογής έχοντας ως κεντρικό πρόβλημα το πως θα φτάσουμε ομόφωνα σε μια κοινωνικά καλή απόφαση έχοντας ως δεδομένο τις προτιμήσεις των ψηφοφόρων πάνω σε ένα σύνολο από υποψηφίους. Πολλά συστήματα ψηφοφορίας έχουν εμφανιστεί στη σχετική βιβλιογραφία από τότε που οι Borda και Marquis de Condorcet πρότειναν στα τέλη του 18ου αιώνα τα πρώτα συστήματα. Ενώ οι περισσότερες από τις σχετικές έρευνες εστιάζουν στις ιδιότητες των συστημάτων ψηφοφορίας για κυβερνητικές εκλογές ή λήψη αποφάσεων σε επιτροπές, η εμφάνιση εφαρμογών μεγάλης κλίμακας για εξόρυξη πληροφορίας, κατάταξη, και ανάκτηση έχει βάλει την ψηφοφορία στην ημερήσια διάταξη της έρευνας της επιστήμης των υπολογιστών. Όντως, προβλήματα σαν την κατάταξη συνόλων μπορούν να θεωρηθούν ως προβλήματα εκλογών. Στα προβλήματα κατάταξης συνόλων, δίδεται ένα σύνολο από διαφορετικές κατατάξεις (π.χ. τα αποτελέσματα από διαφορετικές μηχανές αναζήτησης ιστοσελίδων σε ένα συγκεκριμένο ερώτημα) για το ίδιο σύνολο δεδομένων (π.χ. ιστοσελίδες σχετικές με το ερώτημα), και ο σκοπός είναι να επιλεγεί μια μοναδική κατάταξη που είναι κοντά σε όλες τις κατατάξεις σύμφωνα με ένα καλώς ορισμένο κριτήριο. Σε αυτό το παράδειγμα, οι διαφορετικές μηχανές αναζήτησης είναι οι ψηφοφόροι και κάθε σελίδα αντιστοιχεί σε ένα υποψήφιο, και ο σκοπός σύμφωνα με το οποίον υπολογίζεται η μοναδική κατάταξη είναι ο κανόνας ψηφοφορίας. Είναι φανερό ότι σε τέτοιες εφαρμογές η απόφαση για το ποιος είναι ο νικητής των εκλογών δεν είναι το μόνο πρόβλημα, συνήθως απαιτείται η πλήρης κατάταξη των υποψηφίων. Στην εργασία αυτή γίνεται αρχικά μια προσπάθεια καταγραφής των κυριότερων συστημάτων κοινωνικής επιλογής. Κατά κύριο λόγο εστιάζουμε στη μέθοδο που πρότεινε ο Dodgson και ακολούθως στην μέθοδο του Young. Αυτοί οι κανόνες ψηφοφορίας έχουν σχεδιαστεί για να βρίσκουν τον υποψήφιο που είναι πιο κοντά στο νικητή κατά Condorcet. Το σκορ ενός δεδομένου υποψηφίου είναι γνωστό ότι είναι δύσκολο να υπολογιστεί και για τους δυο κανόνες. Σε αυτήν την εργασία, προτείνουμε για την μέθοδο του Dodgson δυο προσεγγιστικούς αλγόριθμους. Πιο συγκεκριμένα παρουσιάστηκαν και αναλύθηκαν δυο προσεγγιστικοί αλγόριθμοι υπολογισμού του Dodgson σκορ ενός υποψηφίου σε μία εκλογή Dodgson με N υποψηφίους, ένας άπληστος ντετερμινιστικός και ένας πιθανοτικός. Και οι δυο αλγόριθμοι έχουν λόγο προσέγγισης Ο (log N). Επίσης αποδεικνύουμε ότι ο άπληστος αλγόριθμος είναι βέλτιστος μέχρι ένα παράγοντα της τάξης του 2 εκτός αν όλα τα προβλήματα που ανήκουν στο ΝΡ έχουν υπο-εκθετικού (quasi-polynomial) χρόνου αλγορίθμους. Παρόλο που ο άπληστος αλγόριθμος είναι υπολογιστικά ισχυρότερος, ο πιθανοτικός μας αλγόριθμος έχει πλεονέκτημα υπό την οπτική της θεωρίας κοινωνικής επιλογής. Ακόμη, δείχνουμε ότι ο υπολογισμός οποιασδήποτε ικανοποιητικής προσέγγισης που παράγεται από τον κανόνα του Dodgson είναι υπολογιστικά δύσκολη. Αυτό παρέχει μια θεωρητική εξήγηση από σκοπιά υπολογιστικής πολυπλοκότητας για τις μεγάλες διαφορές που έχουν παρατηρηθεί στην θεωρία κοινωνικής επιλογής όταν συγκρίνονται οι εκλογές Dodgson με απλούστερους κανόνες ψηφοφορίας. Τέλος δείχνουμε ότι το πρόβλημα υπολογισμού του Young σκορ είναι ΝΡ-δύσκολο να προσεγγιστεί υπό οποιονδήποτε παράγοντα. Τα κυριότερα αποτελέσματα που εκπονήθηκαν σε αυτήν την εργασία παρουσιάστηκαν στο συνέδριο ACM-SIAM Symposium on Discrete Algorithms (SODA09). / Voting is a popular way for distributed decision making and has traditionally been the subject of Social Choice Theory with the central issue being how to reach consensus on a socially good decision given the preferences of voters on a set of alternatives (or candidates). Several voting systems have appeared in the related literature since the first voting systems were proposed by Borda and Marquis de Condorcet at the end of the 18th century. While most of the related studies have focused on properties of voting systems for government elections or decision making in committees, the emergence of large-scale applications for data mining, classification, and retrieval has put voting in the research agenda of Computer Science. Indeed, problems like rank aggregation can be thought of as elections. In rank aggregation, we are given a set of different rankings (e.g., the results from different web search engines on a particular query) over the same set of data (e.g., web pages related to the query), and the objective is to select a single ranking which is close to all rankings according to a well-defined criterion. In this example, the different web search engines are the voters, each web page corresponds to a candidate, and the objective according to which the single ranking is computed is the voting rule. Clearly, in such applications, deciding the winner of the election is not the only issue; usually, the ranking of the candidates is required as a complete answer. In this thesis firstly we familiarize the reader with the main different methods of social choice theory. We focus on two methods, the Dodgson method and the Young one. These two voting rules have been designed in order to find the candidate which is closer to the Condorcet winner, under two different significances of approach. The score of a given candidate is known that is NP-hard to compute for the two voting rules. So we suggest two approximation algorithms for the Dodgson's method. These two approximation algorithms compute the Dodgson score of a given candidate in an election of N candidates. The first one is a greedy deterministic algorithm while the second one is randomized. Both algorithms have approximation ratio of O(logN). While the greedy algorithm is computationally superior in every way, we show that the randomized has the advantage of being monotonic, which is a desirable property from a social choice point of view. We further observe that it follows from the work of McCabe-Dansted that the Dodgson score cannot be approximated within sublogarithmic factors by polynomial-time deterministic algorithms unless P = NP, and by polynomial-time randomized algorithms unless RP = NP. We prove a more explicit inapproximability result of (1-ε) lnm, under the assumption that problems in NP do not have algorithms running in quasi-polynomial time; this implies that the approximation ratio achieved by our greedy algorithm is optimal up to a factor of 2. Some of the results mentioned above establish that there are sharp discrepancies between the Dodgson ranking and the rankings produced by other rank aggregation rules. Some of these rules (e.g., Borda and Copeland) are polynomial-time computable, so the corresponing results can be viewed as negative results regarding the approximability of the Dodgson ranking by polynomial-time algorithms. We show that the problem of distinguishing between whether a given alternative is the unique Dodgson winner or in the last O(√m) positions in any Dodgson ranking is NP-hard. Finally, we found the following result : it is NP-hard to approximate the Young score within any factor. Speciφιcally, we show that it is NP-hard to distinguish between the case where the Young score of a given alternative is 0, and the case where the score is greater than 0. As a corollary we obtain an inapproximability result for the Young ranking. The results of this thesis were presented in ACM-SIAM Symposium on Discrete Algorithms (SODA09).