Bayesian nonparametric tests via sliced inverse modeling

We study the problem of independence and conditional independence tests between categorical covariates and a continuous response variable, which has an immediate application in genetics. Instead of estimating the conditional distribution of the response given values of covariates, we model the conditional distribution of covariates given the discretized response (aka "slices"). By assigning a prior probability to each possible discretization scheme, we can compute efficiently a Bayes factor (BF)-statistic for the independence (or conditional independence) test using a dynamic programming algorithm. Asymptotic and finite-sample properties such as power and null distribution of the BF statistic are studied, and a stepwise variable selection method based on the BF statistic is further developed. We compare the BF statistic with some existing classical methods and demonstrate its statistical power through extensive simulation studies. We apply the proposed method to a mouse genetics data set aiming to detect quantitative trait loci (QTLs) and obtain promising results.Comment: 32 pages, 7 figure

A programmable integrated power supply for the electrostatic-drive micromotor

A 6-phase bipolarized, high-voltage power supply with rectangular pulse shape has been designed to study the special operational characteristics of various electrostatic-drive micromotors. In particular the design powers the variable-capacitance side-drive micromotor. This power supply provides variable frequency, variable voltage, and variable duty-cycle control. Simulation has been used extensively in the design and design verification. The bipolarization (dual voltage polarity) of each pair of the phases reduces physical clamping of the rotor to the electrical shield beneath it. Thus, bipolarization of the voltage supplied to the stator nodes reduces charge build-up on the rotor. The output frequency range varying from 1Hz to 40KHz has been achieved. This supply frequency range corresponds to motor rotational speed range of 5rpm to 200Krpm, for a micromotor with 12 stator poles and 8 rotor poles (3:2 architec-ture). The voltage amplitudes of all six phases can be varied from 20 to 200Volts. The duty cycle of each phase can be changed by means of a parallel register. The output with variable duty cycle has been obtained, changing from 50% non-overlapping to 33% overlapping. The power supply with 6-phase bipolarized output, variable frequency, and variable voltage output has been constructed with prototyping wire wrap boards, and assembled in a card cage. The power supply is shown to meet the design specification

Generalization Bounds for Representative Domain Adaptation

In this paper, we propose a novel framework to analyze the theoretical properties of the learning process for a representative type of domain adaptation, which combines data from multiple sources and one target (or briefly called representative domain adaptation). In particular, we use the integral probability metric to measure the difference between the distributions of two domains and meanwhile compare it with the H-divergence and the discrepancy distance. We develop the Hoeffding-type, the Bennett-type and the McDiarmid-type deviation inequalities for multiple domains respectively, and then present the symmetrization inequality for representative domain adaptation. Next, we use the derived inequalities to obtain the Hoeffding-type and the Bennett-type generalization bounds respectively, both of which are based on the uniform entropy number. Moreover, we present the generalization bounds based on the Rademacher complexity. Finally, we analyze the asymptotic convergence and the rate of convergence of the learning process for representative domain adaptation. We discuss the factors that affect the asymptotic behavior of the learning process and the numerical experiments support our theoretical findings as well. Meanwhile, we give a comparison with the existing results of domain adaptation and the classical results under the same-distribution assumption.Comment: arXiv admin note: substantial text overlap with arXiv:1304.157

Sol-Gel Processes of Functional Powders and Films

The key principles of sol-gel process and its characteristics are outlined and its major control parameters are summarized. Different samples of functional powders and films with magnetic, optical, and dielectric properties prepared by the sol-gel method are described. To determine the relationship between microstructure and properties, the effects of preparation conditions on the size and microstructure and electric properties, dielectric properties, optical properties, and magnetic properties are analyzed