Design of improved rail-to-rail low-distortion and low-stress switches in advanced CMOS technologies

This paper describes the efficient design of an improved and dedicated switched-capacitor (SC) circuit capable of linearizing CMOS switches to allow SC circuits to reach low distortion levels. The described circuit (SC linearization control circuit, SLC) has the advantage over conventional clock-bootstrapping circuits of exhibiting low-stress, since large gate voltages are avoided. This paper presents exhaustive corner simulation results of a SC sample-and-hold (S/H) circuit which employs the proposed and optimized circuits, together with the experimental evaluation of a complete 10-bit ADC utilizing the referred S/H circuit. These results show that the SLC circuits can reduce distortion and increase dynamic linearity above 12 bits for wide input signal bandwidths.

A similarity measure for music signals

One of the goals in the field of Music Information Retrieval is to obtain a measure of similarity between two musical recordings. Such a measure is at the core of automatic classification, query, and retrieval systems, which have become a necessity due to the ever increasing availability and size of musical databases. This paper proposes a method for calculating a similarity distance between two music signals. The method extracts a set of features from the audio recordings, models the features, and determines the distance between models. While further work is needed, preliminary results show that the proposed method has the potential to be used as a similarity measure for musical signals.

An integrated measure of student perceptions of feedback, engagement and school identification

Teacher feedback influences student learning, identity construction and trajectories. This study tests the measurement properties of a questionnaire designed to assess (a) student perceptions about teacher feedback; (b) student identification with school, and; (c) student engagement. 1089 students in grades 6 through 10 (mean age 13.4) participated in the study. Factor analyses yield dimensions of School Identification, Effective Feedback, Person-Centered Feedback, Engagement, and Social Acceptance. Internal consistency for principal dimensions varied between .77 and .89. The instrument is suitable for assessing student school identification, behavioral engagement, and perceptions of teacher feedback.