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).

Santrauka Magistro darbe nagrinėjamos naujos pianistų ugdymo paradigmos galimybės. Nustatyta, kad iš visų šiandieninę vaikų muzikos mokyklą baigusių mokinių tik 5% renkasi tolesnį būsimo muziko profesionalo kelią – pratęsia mokslus formalaus muzikinio ugdymo įstaigose (konservatorijose, menų mokyklose, LMTA). Taigi 95% moksleivių, neketinančių muzikos mokslus pratęsti toliau, yra taikomi nedidelio procento ugdytinių poreikius atitinkantys ugdymo metodai –- aukšti, profesionaliam ugdymui reikalingi mokymosi standartai. Tokie kontrastingi šiuolaikinėse muzikinio, taip pat ir fortepijono mokymo procentiniai rodikliai įrodo akivaizdų nuostatų diferencijavimo stygių. Šiame darbe modeliuojamas skirtingo ugdymosi alternatyvų vaikų muzikos mokyklų fortepijono skyriuose radimasis – naujas, įvairius moksleivių ugdymosi tikslus ir galimybes atspindintis reiškinys. Empirinio tyrimo, atlikto vaikų muzikos mokyklose, tikslas – nustatyti mokymo/si skambinti fortepijonu muzikos mokyklose ypatumus. Tyrimo objektas – mokymas/is skambinti fortepijonu muzikos mokyklose. Tyrimo metu atlikti šie uždaviniai: mokytojų anketine apklausa išsiaiškinta, kaip vaikai mokomi skambinti fortepijonu, nustatytas mokytojų požiūris į diferencijuoto ugdymosi radimąsi ir galimus tokio mokymo kriterijus fortepijono skyriuje. Anketine apklausa ištirtas mokinių požiūris į fortepijono mokymą/si. Tyrimo metodas – anketinė apklausa, interviu. Apklausti 64 fortepijono specialybės mokytojai ir 90 fortepijono specialybės... [toliau žr. visą tekstą] / The Master thesis analyses new possibilities of pianist teaching paradigms. The conducted research has shown that only 5 % of all contemporary music school graduates choose to be professional musicians by studying at schools of formal music education (conservatoires, art schools, LAMT). Therefore, teaching methods (high teaching standards necessary for professional education) corresponding the needs to a small number of students are applied to 95 % of students who do not intend to continue their studies as professionals. A big contrast in percentage points to an evident lack of attitude differentiation in contemporary music and piano teaching issues. This work modulates different educational alternatives in children‘s music schools and piano departments; a new phenomenon, reflecting different students educational objectives and possibilities. The objective of empirical research conducted at children’s music schools was to identify the peculiarities of teaching/learning playing the piano at music schools. The object of the research is teaching and learning playing the piano at music schools. During the research the several tasks were accomplished; teachers‘ questionnaires pointed out how children are taught to play the piano, teachers‘ attitude towards differentiating education and possible criterion of such education at piano departments was determined. Questionnaires established students‘ attitude to teaching and learning the piano. The research method applied was a... [to full text]

Dans un contexxte de sélection sexuelle, les signaux émis par les mâles sont censés refléter honnêtement leur condition. Etant donné que la condition est un concept multifactoriel, il a été propposé que les différentes composantes des signaux sexuels reflètent différents aspects de la condition de l'émetteur (Hypothèse des messages multiples). Ma thèse a pour but de tester la condition-dépendance des signaux sexuel et l'hypothèse des messages multiples en manipulant différents aspects de la condition mâle ; et d'étudier les moyens de contourner un système de signalement honnête par des tactiques de reproduction alternatives. Nous avons conduit ces expériences chez Hyla arborea, espèce chez laquelle les mâles émettent des signaux comprenant des composantes accoustiques et visuelles impliquées dans le choix du partenaires sexuel. Nos résultats suggèrent que le taux de chant intra-bout, une propriétédynamique, est un indicateur de la condition actuelle, alors que la fréquence dominante, une prpriété statique du chant, semble indépendante de la condition actuelle mais liée à la condition passée. Les composantes visuelles du signal sont indépendantes des variations du statut mutirtionnel à court terme mais pourraient être des indicateurs de la condition passée. L'adoption d'une tactique satellite dépend plus de la condition passée que de l'actuelle. Plusieurs composantes du signal sont liées à différents aspects de la condition du mâle, ce qui supporte l'hypothèsedes messages multiples. CEpendant, les relations entre les composantes et les aspects de la condtion sont faibles et nous poussent à considérer également la dynamique évolutive des systèmes de signalements.

Tiriamojo darbo objektas: Šventosios uostas ir Baltijos priekrantė. Tiriamojo darbo tikslas: susipažinti su Šventosios uosto rekonstrukcijos galimybių studijomis bei poveikio aplinkai ataskaita, išanalizuoti numatomas uosto rekonstrukcijos alternatyvas ir ištirti papildomą uosto rekonstrukcijos alternatyvą (pakeisti įplaukos kanalo kryptį) hidrodinaminiu ir nešmenų pernašos aspektais. Tiriamojo darbo uždaviniai: 1. Atlikti literatūros apžvalgą apie jūrų uostus Lietuvoje ir jų poveikį aplinkai. 2. Susipažinti su Šventosios uosto rekonstrukcijos poveikio aplinkai vertinimo (PAV) ataskaita. 3. Įsisavinti skaitmeninio modeliavimo sistemos MIKE 21 bangų (NSW), hidrodinaminį (HD) ir nešmenų pernašos (ST) modelius. 4. Sudaryti papildomą uosto rekonstrukcijos alternatyvą ir nustatyti jos poveikį hidrodinaminiams ir nešmenų pernašos procesams Baltijos priekrantėje. 5. Palyginti papildomos uosto rekonstrukcijos alternatyvos ir PAV ištirtų alternatyvų poveikį hidrodinaminiams ir nešmenų pernašos procesams Baltijos priekrantėje. Tiriamojo darbo metodika: literatūros apžvalgos skyrius rašomas referatyviai, analizuojant mokslinius šaltinius, didžiausią dėmesį atkreipiant į Šventosios uosto raidą ir poveikį aplinkai. Atliekamas rekonstrukcijos alternatyvų modeliavimas MIKE 21 skaitmeninio modeliavimo programa. Atliekamas modeliavimo rezultatų palyginimas. Tiriamojo darbo rezultatai: 1. Literatūros analizėje apžvelgta bendra Lietuvos uostų būklė, Šventosios uosto istorinė raida... [toliau žr. visą tekstą] / Object of the research: Port of Šventoji and Baltic Sea coast. Aim of the research: Become acquainted with Port of Šventoji reconstruction feasibility studies and environmental impact report, to analyze the expected port reconstruction alternatives and investigate additional port reconstruction alternative with a change of port entrance to south-west direction, also alternatives are evaluated on the hydrodynamic and sediment transport processes in the Baltic coast region. Objectives of the research: 1. Perform literature review of the ports in Lithuania and their impact on the environment. 2. Become acquainted with environmental impact report and port of Šventoji reconstruction possibilities. 3. To become familiar with digital modeling tool MIKE 21 wave (NSW), hydrodynamic (HD) and sediment transportation (ST) models. 4. To create additional reconstruction alternative of the port and determine its impact on the Baltic coast region and hydrodynamic processes. 5. To compare hydrodynamic and sediment transport modeling results of additional alternative and alternatives of the EIA, Research methods: Literature review section is written essay style, followed by analysis of scientific sources, focusing on the Šventoji port development and environmental impact. Reconstruction alternatives modeling is performed by using digital modeling tool MIKE 21. Comparison of simulation results is performed. Research results: 1. In the literature analysis, general condition of... [to full text]

Relational interdependent self-construal (RISC) refers to the self as defined by relationships with others. My research examined the effects of RISC and stress on relationship satisfaction and alternatives to the current partner in romantic relationships. This research also examined whether RISC was correlated with higher quality and quantity of social support and whether social support acted as a buffer during times of stress. In this study, 196 participants were measured on their level of RISC, social support, general health, positive and negative affect, relationship satisfaction, and attention to alternative partners. Participants were randomly assigned to either a stress condition or a non-stress condition. Participants completed two stress manipulations and an implicit measure of attention to alternative partners based on a reaction time task. Using Pearson correlations I found that RISC and social support were positively correlated. I also found that stress in the past month was correlated with poorer health, higher negative affect, and lower positive affect. Furthermore, regressions indicated that individuals high in RISC had higher satisfaction in their romantic relationship; however, the interaction between RISC and stress did not predict relationship satisfaction.

I argue that despite the fact that there can be no strong refutation of skepticism it remains that ignoring skeptical hypotheses and relying on one’s sensory experience are both sound epistemic practices. This argument comes in the form of arguing that we are justified in ignoring skeptical hypotheses on the grounds that (1) they are merely logically possible, and (2) the merely logically possible is rarely relevant in the context of everyday life. I suggest that (2) is true on the grounds that the context of everyday life is one in which our epistemic pursuit of truth is mixed with other pragmatic goals. The result of this mix is that the pursuit of truth can conflict with our goal of avoiding error in such a way that we must choose to prioritize one goal over the other. The above choice implies that skepticism comes at an epistemic cost not acknowledge in the contemporary literature on external world skepticism. This epistemic cost of skepticism means that the relative risk of error involved in relying on sensory experience is not as epistemically problematic as has often been assumed. These considerations allow an anti-skeptical position in which relying on sensory experience is prima-facie justified despite the possibility of being a brain in a vat. In this paper I explore what such a position might look like and what the implications of such a view might be for relevant alternatives positions, the closure debate, and the concept of differing epistemic perspectives in contemporary epistemology.

Following three major mining accidents in 2006, the MINER Act of 2006 was enacted by MSHA and required every underground coal mine to install refuge alternatives to help prevent future fatalities of trapped miners in the event of a disaster. The following research was performed in response to NIOSH’s call for the investigation into new refuge alternatives. A 15 psi safe haven polycarbonate wall for use in underground coal mines was designed and modeled using finite element modeling in ANSYS Explicit Dynamics. The successful design was tested multiple times in both half-scale and small scale using a high explosive shock tube to determine the walls resistance to blast pressure. The safe haven wall design was modeled for an actual underground coal mine environment to determine any responses of the wall within a mine. A full scale design was fabricated and installed in an underground coal mine to determine any construction constraints and as a final step in proof of concept for the safe haven design.

The aim of the present study was to investigate the experiences and attitudes concerningpreimplantation genetic diagnosis (PGD) among the couples that have undergone PGD in Sweden.PGD is an alternative to conventional prenatal diagnosis for couples with a high risk of having a childwith genetic disease. Couples opting for PGD have to perform in vitro fertilisation, generatedembryos are subjected to biopsy and diagnosis, and healthy embryos can be transferred to the femaleuterus. Hopefully a pregnancy will be established. However, PGD is a strategy that implies bothphysical and psychological stress, and it is not obvious that this is an easier alternative than prenataldiagnosis. A questionnaire was sent to 116 couples that had carried out at least one PGD treatmentcycle. The response rate was 89%, thus almost all couples treated in Sweden since the start in 1995was represented. Results: The stress, both psychologically and physically, caused by the PGD treatment was evaluatedsomewhere between “As expected” and “More stressful than expected”. The stress experienced duringthe PGD treatments was not associated with the couples’ previous reproductive experiences. The mostphysical stressful event was the oocyte retrieval and the most psychologically stressful period was“waiting for a possibly/ hopefully embryo transfer”.The majority of couples that had performed prenatal diagnosis on a spontaneous pregnancy andexperienced a PGD treatment reported that PGD was more physically stressful (54%), but that prenataldiagnosis was more psychologically stressful (51%). The couples reported the reproductivealternatives chosen after PGD closure, and couples performing PGD at the present rated futurereproductive alternatives. Results indicated that ocyte- and sperm donations were a less attractivealternative than for example adoption. Participants in the study also had the opportunity to state forwhom /which indications PGD should be an option. Conclusion: The stress associated with performing PGD or prenatal diagnosis is extensive and noneof the alternatives is an obvious choice. PGD was reported as more physical stressful, but prenataldiagnosis was more psychologically stressful. The reproductive pathways chosen after PGD closurewas reported, and surprisingly sperm and oocyte donations were not attractive alternatives. The choiceof reproductive alternatives might be influenced by the information and support provided by thehealthcare personal. Knowledge about the experience of PGD treatments is of great importance forthose that meet these couples for genetic and reproductive counselling, in order to give them propercare and to better meet their demand of information and support.

Sustainable transport planning is a complex issue and has become a great challenge for today’s decision makers. One of the biggest concerns is how sustainable mobility can be reached; where social and economic interests can work together with environmental interests. By looking into a special case of transport planning in Åriket, Uppsala this paper analyses the decision making process as well as the response from other stakeholders presented as contesting story lines. The results show there are weaknesses in the planning process, where too few alternatives have been looked at and the methods used has not been able to handle the complex issues of sustainable development in an adequate way. From the contested story lines the different opinions in the question has been identified as either being a part of the old conventional transport paradigm or a part of the new sustainable mobility paradigm, which can be used as a guideline for the decision makers in what way to go for reaching sustainable mobility.