Thesis (Ph.D.)--University of Alberta, 2009. / A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Centre for Neuroscience. Title from pdf file main screen (viewed on October 11, 2009). Includes bibliographical references.

Στη διατριβή αυτή θα μελετήσουμε μονότονες ποσότητες στα πλαίσια συνδυασμένων γεωμετρικών ροών. Πιο συγκεκριμμένα, εστιάζοντας την προσοχή μας στη περίπτωση των σολιτονίων Ricci, ως περιβάλλοντες χώρους, θα θεωρήσουμε λύσεις της εξίσωσης θερμότητας ολοκληρωμένες πάνω σε εμβαπτισμένες υποπολλαπλότητες οι οποίες εξελίσσονται χρονικά με τη ροή μέσης καμπυλότητας. Επιπρόσθετα, στη περίπτωση του συνδυασμού αντίστροφης ροής Ricci, ροής μέσης καμπυλότητας, όταν ο περιβάλλων χώρος είναι Kahler, η λύση της αντίστροφης εξίσωσης θερμότητας, ολοκληρωμένη πάνω στην υποπολλαπλότητα αποτελεί μονότονη ποσότητα. / -

abstract: Small metallic parts of size less than 1mm, with features measured in tens of microns, with tolerances as small as 0.1 micron are in demand for the research in many fields such as electronics, optics, and biomedical engineering. Because of various drawbacks with non-mechanical micromanufacturing processes, micromilling has shown itself to be an attractive alternative manufacturing method. Micromilling is a microscale manufacturing process that can be used to produce a wide range of small parts, including those that have complex 3-dimensional contours. Although the micromilling process is superficially similar to conventional-scale milling, the physical processes of micromilling are unique due to the scale effects. These scale effects occur due to unequal scaling of the parameters from the macroscale to the microscale milling. One key example of scale effects in micromilling process is a geometrical source of error known as chord error. The chord error limits the feedrate to a reduced value to produce the features within machining tolerances. In this research, it is hypothesized that the increase of chord error in micromilling can be alleviated by intelligent modification of the kinematic arrangement of the micromilling machine. Currently, all 3-axis micromilling machines are constructed with a Cartesian kinematic arrangement with three perpendicular linear axes. In this research, the cylindrical kinematic arrangement is introduced, and an analytical expression for the chord error for this arrangement is derived. The numerical simulations are performed to evaluate the chord errors for the cylindrical kinematic arrangement. It is found that cylindrical kinematic arrangement gives reduced chord error for some types of the desired toolpaths. Then, the kinematic redundancy is introduced to design a novel kinematic arrangement. Several desired toolpaths have been numerically simulated to evaluate the chord error for kinematically redundant arrangement. It is concluded that this arrangement gives up to 5 times reduced error for all the desired toolpaths considered, and allows significant gains in allowable feedrates. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2014

Context: Chat applications have been around since the beginning of the modern internet. Today, there are many different chat systems with various communication solutions, but only a few utilize the fully decentralized Peer-to-Peer concept. Objectives: In this report, we want to investigate to see if a fully decentralized P2P concept is a suitable choice for chat applications. In order to investigate, a P2P architecture was selected and a simulation was implemented in Java. The simulation was used to make a performance evaluation in order see if the P2P concept could meet the requirements of a chat application, and to identify problems and difficulties. Methods: Two main methods were used in this thesis. First, a qualitative design method was used to identify and discuss different possibilities of designing a distributed chat application. Second, a performance evaluation was conducted to verify the selected and implemented mechanisms are able to obtain their general performance capabilities and to tune them towards anticipated performance. Results: The simulation proved that a decentralized P2P system can scale and find resources in a network quite efficiently without the need of any centralized service. It also proved to be simpler for the user to use the P2P concept, as no special configurations are needed. However, the selected protocol (Chord) had problems with high rates of churn, which could cause problems in big chat environments. The P2P concept was also shown to be highly complex to implement. Conclusion: P2P technology is a more complex technology, but it gives the host a lower cost in terms of hardware and maintenance. It also makes the system more robust and fault-tolerant. As we have seen in this report, P2P can scale and find other resources efficiently without the need of a centralized service. However, it will consume more power for each user, which makes mobile devices bad peers.

This research focuses on the redesign of trust and reputation algorithms in the context of hierarchically structured Peer-to-Peer (P2P) networks with Chord, a scalable P2P lookup service for Internet applications. Chord, which is an open source project, is an overlay network based on a distributed hash table(DHT), and all peers in Chord are arranged around a circle. In this work, we propose four adapted trust and reputation algorithms for hierarchically structured P2P networks: EigenTrust, PowerTrust, Absolute Trust and NodeRanking. EigenTrust is one of the most well-known trust and reputation algorithms, as well as the most simple. To calculate the reputation, EigenTrust needs to normalize trust and rely on pre-trusted peers. Like EigenTrust, PowerTrust relies on feedback and the use of a distributed ranking mechanism. It chooses a limited number of power nodes with a high reputation. By combining a random walk strategy and the power nodes, it improves accuracy of global reputation. AbsoluteTrust does not require normalization of trust, pretrusted peers or any centralized authority. Weighted average combined with feedback from peers is employed to determine trust. NodeRanking relies on both individual reputation and social relationship to compute the trust value. NodeRanking evaluates reputation using local information. A node's reputation value can be readily determined by the number of references from other nodes in the network. These adapted algorithms are capable of handling a huge number of nodes disseminated in different rings, which improves complexity and reduces the number of malicious nodes in a hierarchical context. Furthermore, we describe the components of the hierarchical model architecture and present and discuss the results from the experiments. These experiments are employed to verify and compare reduction of downloads from malicious peers, load distribution and residual curl in at structured networks and in hierarchically structured networks.

With growing number of devices connected to the network, there is a greater need for use of Peer-to-Peer (P2P) networks and distributed P2P protocols.Devices participating in the P2P network do not usually need to use any central server that links up connections. It has many advantages but it needs to use so-called overlay network that consists of protocols used for traffic routing and decision making. Protocols used in today’s P2P networks are mostly not considerate of particular participating nodes and all the nodes in the network are usually equal. This can have negative impacts on network performance. In order to avoid or reduce some unwanted negative impacts, it would be advantageous if the overlay network could route traffic and make decisions according to context information like battery levels or connection speeds. This work reviews a few popular P2P overlay networks and based on that it introduces an improvement of one of them – Chord. The structure of the improved version of the Chord protocol called Context-Aware Chord is described. Then results of the evaluation are presented. With a use of the improved protocol, nodes can participate longer in the network and throughput of lookup messages is improved.

Tonality is a term often used to describe the music of the common practice period (roughly 1600-1900). This study examines the music of mid twentieth-century jazz composer Thad Jones in light of an extended common practice, explicating ways in which this music might be best understood as tonal. Drawing from analyses of three of Jones’s big band compositions: To You, Three and One, and Cherry Juice, this study examines three primary elements in detail. First is Jones’s use of chord-scale application techniques in the orchestration over various chordal qualities represented by the symbols, revealing traditional as well as innovative methods by Jones. Second is Jones’s use of harmonic progressions, demonstrating his connection to past practice as well as modern jazz variations. Third is Jones’s use of contrapuntal connections and their traditional relationship to functional tonality, but in a chromatic scale-based environment. Jones’s music is presented in this study to demonstrate a tonal jazz common practice that represents an amalgamation of traditions including twentieth-century scale-based procedures, Renaissance and early twentieth-century modality, eighteenth- and nineteenth-century voice leading schemas, and Baroque and Classical descending-fifth progressions. Also included as an appendix is a list of possible note errors in the published scores of To You, Three and One, and Cherry Juice.

京都大学 / 新制・課程博士 / 博士(情報学) / 甲第23540号 / 情博第770号 / 新制||情||131(附属図書館) / 京都大学大学院情報学研究科知能情報学専攻 / (主査)准教授 吉井 和佳, 教授 河原 達也, 教授 西野 恒, 教授 鹿島 久嗣 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(生命科学) / 甲第18484号 / 生博第313号 / 新制||生||41(附属図書館) / 31362 / 京都大学大学院生命科学研究科統合生命科学専攻 / (主査)教授 上村 匡, 教授 米原 伸, 教授 見学 美根子 / 学位規則第4条第1項該当 / Doctor of Philosophy in Life Sciences / Kyoto University / DFAM

Cadences are orderly progressions of chords which occur in classical and contemporary Western music. They can serve as anchoring points for the perception of musical key and of tonality. The rules governing the structure and usage of cadences have been set forth in music theory. In a series of experiments, listeners were able to rate the stability of simple two-chord cadences without explicit knowledge of music theoretical concepts. The stability ratings obtained for the cadences presented in these experiments were affected by the listener's musical training (inexperienced or formally trained), by the cadence type (chord progression moving toward or away from the tonic), by the position of the root (in the lowest or uppermost note position of chord) by the direction of cadence resolution (upward or downward pitch change). and by the tonal context. The tonal context was an ascending or descending diatonic scale in the key of G-major or C-major played before each cadence trial. Two hypothetical listening strategies were introduced as possible ways of perceiving musical cadences. Melody-tracking was defined as a simple analytic listening strategy which focused on the soprano voice of each chord in a cadence. Voice-tracking was defined as a flexible strategy which allowed the listener to focus on either the soprano or the bass voice in the triad sequence. Musically trained listeners' ratings generally conformed to the voice-tracking strategy. Their ratings followed conventional standards consistently and accurately. They rated G-C cadences most stable in a C-major context. and C-G cadences most stable in a G-major context. Untrained listeners' ratings did not consistently show this effect of key context. Their ratings generally conformed to the melody-tracking strategy. They considered downward resolution of a cadence more stable than upward resolution, and they gave higher stability ratings to cadences when the soprano voice instead of the bass voice led the cadence. All listeners tended to rate plagal cadences as more stable than imperfect cadences, and perfect cadences as more stable than other cadences. They also generally gave higher stability ratings to soprano-led cadences than to bass-led cadences. The musically untrained listeners were able to assign meaningful stability ratings to cadences. despite their lack of musical terms. The trained listeners appeared to approach the task in a different way. Over the course of formal musical training. trained listeners may have learned to use a more flexible strategy while maintaining a high level of accuracy and consistency in their task performance. / Thesis / Doctor of Philosophy (PhD)