Joint Bayesian Gaussian discriminant analysis for speaker verification

State-of-the-art i-vector based speaker verification relies on variants of Probabilistic Linear Discriminant Analysis (PLDA) for discriminant analysis. We are mainly motivated by the recent work of the joint Bayesian (JB) method, which is originally proposed for discriminant analysis in face verification. We apply JB to speaker verification and make three contributions beyond the original JB. 1) In contrast to the EM iterations with approximated statistics in the original JB, the EM iterations with exact statistics are employed and give better performance. 2) We propose to do simultaneous diagonalization (SD) of the within-class and between-class covariance matrices to achieve efficient testing, which has broader application scope than the SVD-based efficient testing method in the original JB. 3) We scrutinize similarities and differences between various Gaussian PLDAs and JB, complementing the previous analysis of comparing JB only with Prince-Elder PLDA. Extensive experiments are conducted on NIST SRE10 core condition 5, empirically validating the superiority of JB with faster convergence rate and 9-13% EER reduction compared with state-of-the-art PLDA.Comment: accepted by ICASSP201

BEHAVIORAL INTERDEPENDENCE IN PROJECT TEAM COLLABORATION: STUDY OF ENGINEERING STUDENTS’ COLLABORATIVE BEHAVIORS IN HIGH LEVELS OF INTERDEPENDENT TASK SETTINGS

In teamwork learning settings, tasks are often designed at varying levels of interdependence that requires students to complete the tasks by relying only on their team members sharing resources, knowledge, and skills. However, well-structured tasks do not always guarantee task-related collaborative behaviors will occur and are simply not adequate for us to understand the collaboration process and participants’ actual collaborative behaviors. To deepen our understanding of collaboration and explore how increased collaboration may be promoted in high-level interdependent task settings, this study uses behavioral interdependence as an analytical concept to describe and examine individual students’ actual behaviors as they worked collaboratively on an interdependently-structured engineering design project. Behavioral interdependence is “the amount of task-related interaction actually engaged in by group members in completing their work” (Wageman, 2001, p. 207). The concept of behavioral interdependence helps us to understand students’ task-related collaborative behaviors. However, this concept has received scarce attention in collaboration literature. This study was set in a context of college engineering students collaborating on an authentic design project. A descriptive, instrumental two-case study methodology was employed to respond to two main research questions: (1) what individual behaviors are observed in project teams when students were working under the high task interdependence condition and (2) what patterns of team behaviors are observed in such a condition. After examining and comparing two newly-formed college student project teams’ collaborative behaviors in solving an interdependently-structured engineering design project, answers to the research questions help explore how team behavioral patterns formed out of, or were affected by, students’ individual behaviors and how behaviors affected team collaboration and performance. This study resulted in rich descriptions of individual student behaviors and behavior changes, team behaviors and behavior changes, and how individual behaviors were related to team behaviors and overall team collaboration and performance. Results suggested that (1) individual behaviors were closely associated with team behaviors, collaboration, and performance, (2) students’ early behavioral patterns largely predicted their continuous behaviors, (3) urgent deadlines were likely to change behaviors of students who had poor performance in task management and temporal planning, (4) individuals performing better in disciplinary, technical areas tended to have more contribution to and better participation in teamwork, and (5) teams with high levels of behavioral interdependence tended to have better performance in teamwork. Several recommendations are provided for designing instruction in high interdependent task settings such as careful estimation of task completion time considering students’ varying collaboration skills and time management ability levels (task / activity design recommendation), providing suitable scaffolding strategies to support students who are not adequate in technical fields or in skills in areas of self-management, effective communication, and temporal planning (activity preparation recommendation), and paying attention to students’ behaviors at the early stage of their collaboration and providing timely corrective feedback (formative evaluation recommendations)

Art and Chinese Modernity in Connection with Lyon, 1920s-1940s

The twentieth century saw China undergo significant political, social and cultural transformations. Modernisation of art was an integral part of China’s national modernisation project. L’École nationale de beaux-arts de Lyon provided training to at least 58 students from China from 1920 to 1942. Lyon’s connection with modern Chinese art history, however, has not been sufficiently examined. As part of a larger project that examines the process of China’s art modernisation at the beginning of the twentieth century, this paper explores the significance of Lyon as a location of cultural intersection through selected cases of Chinese art students in Lyon. By documenting and analysing the process through which those individual students undertook the challenges of acquiring European concepts and practice of art, this paper demonstrates how the ideal for a modernised Chinese art was modelled largely on French art schools, and how the Chinese implemented their newly acquired knowledge and skills through institutional measures and individual efforts

INFINITE SUMS, PRODUCTS, AND URN MODELS

This paper considers an urn and its evolution in discrete time steps. The urn initially has two different colored balls(blue and red). We discuss different cases where k blue balls (k = 1, 2, 3, ... ) will be added (or removed) at every step if a blue ball is withdrawn, based on the goal of eventually withdrawing a red ball P(R eventually). We compute the probability of eventually withdrawing a red ball with two different methods–one using infinite sums and other using infinite products. One advantage of this is that we can obtain P(R eventually) in a complex but nicely patterned form using one method, and a simple form using the other method. Since the results must be equal, we obtain some interesting identities. We also present a general result and invent new identities, illustrated by an example using the Fibonacci numbers. Additionally, we transform Wallis Product(a) and Wallis Product(b) into urn models. Finally, we illustrate some results by simulating the urn processes in R

Literary responses to bewilderment in western society : a study of Margaret Atwood's novels

Thesis (M.A.) -- University of Adelaide, Dept. of English, 199

Automatic 3D human modeling: an initial stage towards 2-way inside interaction in mixed reality

3D human models play an important role in computer graphics applications from a wide range of domains, including education, entertainment, medical care simulation and military training. In many situations, we want the 3D model to have a visual appearance that matches that of a specific living person and to be able to be controlled by that person in a natural manner. Among other uses, this approach supports the notion of human surrogacy, where the virtual counterpart provides a remote presence for the human who controls the virtual character\u27s behavior. In this dissertation, a human modeling pipeline is proposed for the problem of creating a 3D digital model of a real person. Our solution involves reshaping a 3D human template with a 2D contour of the participant and then mapping the captured texture of that person to the generated mesh. Our method produces an initial contour of a participant by extracting the user image from a natural background. One particularly novel contribution in our approach is the manner in which we improve the initial vertex estimate. We do so through a variant of the ShortStraw corner-finding algorithm commonly used in sketch-based systems. Here, we develop improvements to ShortStraw, presenting an algorithm called IStraw, and then introduce adaptations of this improved version to create a corner-based contour segmentatiuon algorithm. This algorithm provides significant improvements on contour matching over previously developed systems, and does so with low computational complexity. The system presented here advances the state of the art in the following aspects. First, the human modeling process is triggered automatically by matching the participant\u27s pose with an initial pose through a tracking device and software. In our case, the pose capture and skeletal model are provided by the Microsoft Kinect and its associated SDK. Second, color image, depth data, and human tracking information from the Kinect and its SDK are used to automatically extract the contour of the participant and then generate a 3D human model with skeleton. Third, using the pose and the skeletal model, we segment the contour into eight parts and then match the contour points on each segment to a corresponding anchor set associated with a 3D human template. Finally, we map the color image of the person to the 3D model as its corresponding texture map. The whole modeling process only take several seconds and the resulting human model looks like the real person. The geometry of the 3D model matches the contour of the real person, and the model has a photorealistic texture. Furthermore, the mesh of the human model is attached to the skeleton provided in the template, so the model can support programmed animations or be controlled by real people. This human control is commonly done through a literal mapping (motion capture) or a gesture-based puppetry system. Our ultimate goal is to create a mixed reality (MR) system, in which the participants can manipulate virtual objects, and in which these virtual objects can affect the participant, e.g., by restricting their mobility. This MR system prototype design motivated the work of this dissertation, since a realistic 3D human model of the participant is an essential part of implementing this vision