Infrared and Raman spectra of metal-oxygen complexes

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Generating ambiguity in the laboratory

This article develops a method for drawing samples from which it is impossible to infer any quantile or moment of the underlying distribution. The method provides researchers with a way to give subjects the experience of ambiguity. In any experiment, learning the distribution from experience is impossible for the subjects, essentially because it is impossible for the experimenter. We describe our method mathematically, illustrate it in simulations, and then test it in a laboratory experiment. Our technique does not withhold sampling information, does not assume that the subject is incapable of making statistical inferences, is replicable across experiments, and requires no special apparatus. We compare our method to the techniques used in related experiments that attempt to produce an ambiguous experience for the subjects.ambiguity; Ellsberg; Knightian uncertainty; laboratory experiments; ignorance; vagueness JEL Classications: C90; C91; C92; D80; D81

Temperature dependent refractive index of silicon and germanium

Silicon and germanium are perhaps the two most well-understood semiconductor materials in the context of solid state device technologies and more recently micromachining and nanotechnology. Meanwhile, these two materials are also important in the field of infrared lens design. Optical instruments designed for the wavelength range where these two materials are transmissive achieve best performance when cooled to cryogenic temperatures to enhance signal from the scene over instrument background radiation. In order to enable high quality lens designs using silicon and germanium at cryogenic temperatures, we have measured the absolute refractive index of multiple prisms of these two materials using the Cryogenic, High-Accuracy Refraction Measuring System (CHARMS) at NASA Goddard Space Flight Center, as a function of both wavelength and temperature. For silicon, we report absolute refractive index and thermo-optic coefficient (dn/dT) at temperatures ranging from 20 to 300 K at wavelengths from 1.1 to 5.6 microns, while for germanium, we cover temperatures ranging from 20 to 300 K and wavelengths from 1.9 to 5.5 microns. We compare our measurements with others in the literature and provide temperature-dependent Sellmeier coefficients based on our data to allow accurate interpolation of index to other wavelengths and temperatures. Citing the wide variety of values for the refractive indices of these two materials found in the literature, we reiterate the importance of measuring the refractive index of a sample from the same batch of raw material from which final optical components are cut when absolute accuracy greater than +/-5 x 10^-3 is desired.Comment: 10 pages, 8 figures, to be published in the Proc. of SPIE 6273 (Orlando

The Psychometric Assessment Of Job Satisfaction And Its Relation To Stress In The Workplace

The purpose of this dissertation was threefold: (a) to review the current status of the job satisfaction construct, (b) to evaluate how well modern scale development guidelines can produce a satisfaction measure that will be reliable and valid, and (c) to investigate the relationships among satisfaction, stress, and other organizational outcomes.;The first chapter contains three sections. The first is a historical review. The second focuses on measurement concerns from the review. The third section reviews the shortcomings of the literature and how some of these shortcomings might be overcome by considering job satisfaction from a psychometric perspective.;The second chapter outlines the development of a measure of job satisfaction, the Satisfaction Research Questionnaire. The development strategy, readability, reliability, and construct validity are described. An argument is presented for a classification of satisfaction based on model profiles. This classification yielded two bipolar modal profiles of scores.;The third chapter presents empirical results from two samples, a cross-Canada study and a student sample. Five content domains were tapped in this study: (a) respondent information about themselves, (b) response information about their occupations for use in monomethod multitrait comparisons, (c) the Satisfaction Research Questionnaire and another measure (the Job Descriptive Index), (d) a measure of the social desirability response bias, and (e) a measure of the Type A behaviour pattern, as a measure of stress.;The results suggested that the Satisfaction Research Questionnaire would be a viable alternative measure of satisfaction. A robust relationship between satisfaction and stress was evidenced. The differences between this research and historical results were attributed to several factors, including, (a) a modern scale construction approach, (b) the use of modal profile analysis, and (c) a multivariate conceptualization of job satisfaction

Analog Musical Distortion Circuits for Electric Guitars

Distortion, while seen as undesirable in most contexts, has taken a different role in electronic music. Musical distortion refers to nonlinear changes in a waveform, and has been used to change the sounds of electric guitars since the 1940s and 1950s. Originally, distortion was realized with broken tubes in amplifiers or torn speaker cones, but as music evolved, so did the equipment used to produce the desired sounds. Slashed speakers turned into electronic circuits in the mid 1960s, and these electronic circuits are the focus of this paper. Many papers discuss the digitization of analog circuits, but because most analog distortion circuits were commercial products protected by IP laws, there has not been much research in terms of the affects of different circuit topologies and their affects on sound. In this paper, a few topologies are studied with various methods of analog nonlinearities. Two topologies, called distortion and overdrive, were studied. Two nonlinearities were also examined, the diode limiter and the class B amplifier. Overall, 8 circuits were built using various combinations of nonlinearities within each circuit topology. Ultimately, the overdrive topologies were more flexible than the distortion topologies, with the class B overdrive topology being a personal favorite. The only topology that did not work well musically was the class B distortion topology