Fiber optic, Fabry-Perot high temperature sensor

A digital, fiber optic temperature sensor using a variable Fabry-Perot cavity as the sensor element was analyzed, designed, fabricated, and tested. The fiber transmitted cavity reflection spectra is dispersed then converted from an optical signal to electrical information by a charged coupled device (CCD). A microprocessor-based color demodulation system converts the wavelength information to temperature. This general sensor concept not only utilizes an all-optical means of parameter sensing and transmitting, but also exploits microprocessor technology for automated control, calibration, and enhanced performance. The complete temperature sensor system was evaluated in the laboratory. Results show that the Fabry-Perot temperature sensor has good resolution (0.5% of full seale), high accuracy, and potential high temperature ( 1000 C) applications

Getting the Swing of Surface Gravity

Sports are a popular and effective way to illustrate physics principles. Baseball in particular presents a number of opportunities to motivate student interest and teach concepts. Several articles have appeared in this journal on this topic, illustrating a wide variety of areas of physics. In addition, several websites and an entire book are available. In this paper we describe a student-designed project that illustrates the relative surface gravity on the Earth, Sun and other solar-system bodies using baseball. We describe the project and its results here as an example of a simple, fun, and student-driven use of baseball to illustrate an important physics principle

Analysis and preliminary design of optical sensors for propulsion control

A fiber-optic sensor concept screening study was performed. Twenty sensor subsystems were identified and evaluated. Two concepts selected for further study were the Fabry-Perot fiber-optic temperature sensor and the pulse-width-modulated phosphorescent temperature sensor. Various designs suitable for a Fabry-Perot temperature sensor to be used as a remote fiber-optic transducer were investigated. As a result, a particular design was selected and constructed. Tests on this device show that spectral peaks are produced from visible white light, and the change in wavelength of the spectral peaks produced by a change in temperature is consistent with theory and is 36 nm/C for the first order peak. A literature search to determine a suitable phosphor for implementing the pulse-width-modulated fiber optic temperature sensor was conducted. This search indicated that such a device could be made to function for temperatures up to approximately 200 C. Materials like ZnCdS and ZnSe activated with copper will be particularly applicable to temperature sensing in the cryogenic to room temperature region. While this sensing concept is probably not applicable to jet engines, the simplicity and potential reliability make the concept highly desirable for other applications

The cultural commodification of identity : hip-hop authenticity

Title from PDF of title page (University of Missouri--Columbia, viewed on June 30, 2011).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Thesis advisor: Dr. Elizabeth Behm-Morawitz.Includes bibliographical references.M.A. University of Missouri--Columbia 2011.Using the framework of symbolic interactionism, the concept of meaning, when discussing the relationship between hip-hop cultural members and how hip-hop culture is represented in advertisements, can be shaped by certain elements concerning a cultural authenticity. This is shown by how hip-hop cultural members make meaning of the images and messages that derive from commercial advertisements with a hip-hop influence on claims of what is an authentic cultural hip-hop identity. The present study investigated how portrayals of hip-hop artists in U.S. television commercials represented a hip-hop identity, using the analysis of McLeod's (1999) dimensions of hip-hop authenticity. A content analysis of 102 commercials was conducted to explore the relationship between each dimension of hip-hop authenticity and the categories of rap genre, race, and gender of the hip-hop artist featured in the advertisement. There were four significant findings. First, political hip-hop artists geared their message to the Black audience, and secondly, emphasized their connection to the community from which they came more than popular hip-hop artists. Third, Black hip-hop artists' exhibited masculine mannerisms more than White hip-hop artists. Lastly, male hip-hop artists significantly presented more masculine mannerisms than feminine, and female hip-hop artists expressed more feminine mannerisms than masculine; which suggests that there are certain elements involved in gender role performances surrounding hip-hop culture

A Further Note on Formica Exsectiodes Forel

Consideration of the subsoil form and its effect on ant mound distribution within the forest is presented. Active ant mounds are found only where the subsoil is mainly composed of sand and gravel. A report on the discovery of another large complex of ant mounds six miles northwest of New Hartford, Iowa is made

The Perceptions and Determinants of Auditing and Reporting Quality in the Asia-Pacific Region

A country’s institutional environment significantly influences perceptions of auditing and reporting quality (ARQ) at the national level. Relying on a relatively unique measure of ARQ, collated by the World Economic Forum (WEF), we evaluate the influence of nine key isomorphic pressures on the ARQ in 26 Asia-Pacific countries. The results suggest that six of these (the efficacy of the corporate board, securities exchange regulations, reliance on professional management, protection of minority interests, adoption of international financial reporting and prevalence of foreign ownership) have a highly significant influence on the perception of ARQ whereas adoption of international standards on auditing is only moderately significant. However, contrary to expectations, our findings do not support the argument that the efficiency of legal frameworks and political systems significantly influence the perceptions of auditing and reporting quality in the Asia-Pacific region. These results should be of use to investors and the accounting profession in evaluating economic environments