Semiconductor devices and methods

A method of forming a semiconductor device includes the following steps: providing a plurality of semiconductor layers; providing means for coupling signals to and/or from layers of the device; providing a quantum well disposed between adjacent layers of the device; and providing a layer of quantum dots disposed in one of the adjacent layers, and spaced from the quantum well, whereby carriers can tunnel in either direction between the quantum well and the quantum dots.Board of Regents, University of Texas Syste

Endurance and Other Properties at Low Temperatures of Some Alloys for Aircraft Use

The low temperature endurance properties of materials for aircraft construction are not well known. In order to determine them, apparatus for testing endurance at -40 C has been devised. The endurance properties of monel metal, low-carbon stainless steel, "18 and *, " 3 1/2% Ni steel and chromium-molybdenum steel have been determined at -40 C and at room temperature about +20 C. Tensile, impact and hardness tests of these materials have also been made at various temperatures. The results show an increase in endurance limit, tensile strength, and hardness with decreased temperature. Impact strength is, in general, decreased, but of all the alloys tested, only one, low-carbon stainless steel, gives less than 15 ft. lb. Chrpay impact test at -40 C

Aerodynamics of vortex generators

An experimental and theoretical study was undertaken of the separation delay and dramatic boundary-layer thinning that can occur in vortex-generator installations. Wind tunnel measurements of the dynamic-pressure profile downstream of a vortex generator were found to compare under certain conditions with that downstream of a suction slit, while water-tunnel visualization studies of vortex-generator height and geometry suggested optimum configurations, and only a minor effect of base porosity. A series of progressively more complex inviscid flow models was developed to be applied to a 3-D integral boundary-layer code. This code predicted layer thinning downstream of the suction site of the vortex models, and other observed features. Thin-layer Navier-Stokes equations are now being used with the ultimate goal of clarifying the physical processes involved in vortex generator performance and developing calculational procedures capable of predicting it

Polarization Aberrations

The analysis of the polarization characteristics displayed by optical systems can be divided into two categories: geometrical and physical. Geometrical analysis calculates the change in polarization of a wavefront between pupils in an optical instrument. Physical analysis propagates the polarized fields wherever the geometrical analysis is not valid, i.e., near the edges of stops, near images, in anisotropic media, etc. Polarization aberration theory provides a starting point for geometrical design and facilitates subsequent optimization. The polarization aberrations described arise from differences in the transmitted (or reflected) amplitudes and phases at interfaces. The polarization aberration matrix (PAM) is calculated for isotropic rotationally symmetric systems through fourth order and includes the interface phase, amplitude, linear diattenuation, and linear retardance aberrations. The exponential form of Jones matrices used are discussed. The PAM in Jones matrix is introduced. The exact calculation of polarization aberrations through polarization ray tracing is described. The report is divided into three sections: I. Rotationally Symmetric Optical Systems; II. Tilted and Decentered Optical Systems; and Polarization Analysis of LIDARs

Jet Effects on Cylindrical Afterbodies Housing Sonic and Supersonic Nozzles which Exhaust Against a Supersonic Stream at Angles of Attack from 90 to 180

Jet effects on cylindrical afterbodies housing sonic and supersonic nozzle

Decentralized Sewer Unit Packages as an Alternative for Bulloch County to Manage Fast Growth

Throughout the state of Georgia, rural areas rely on septic tanks to dispose of bodily waste for small commercial, industrial, and residential construction. Septic tanks act as the most conventional system when properties fall outside the service areas of municipal and private wastewater treatment facilities. Bulloch County has a vast number of rural dwellings within its boundaries. Moreover, the County experienced a steady 3 to 5% annual growth over the last several years. Therefore, an examination of alternatives to the traditional septic systems is warranted if the County wishes to maintain continued sustainable growth. This study focuses on the factors driving growth in Bulloch county including: population, housing, commercial and industrial development, subdivision development, assessed property values, and future development projections. Next, we compare two waste disposal systems that could substitute for traditional septic systems: a Small Diameter Gravity System (SDGS) and the Bioclere Onsite Wastewater Treatment System. Working Paper Number 2005-001

1962-09-12, Russell to family

This collection contains 38 correspondence written by Lieutenant Russell Knowles, Jr., United States Navy Reserve to his family during the Cold War.https://digitalcommons.chapman.edu/rknowles_correspondence/1029/thumbnail.jp

1962-04-29, Russell to dad

This collection contains 38 correspondence written by Lieutenant Russell Knowles, Jr., United States Navy Reserve to his family during the Cold War.https://digitalcommons.chapman.edu/rknowles_correspondence/1022/thumbnail.jp

1962-11-01, Russell to parents

This collection contains 38 correspondence written by Lieutenant Russell Knowles, Jr., United States Navy Reserve to his family during the Cold War.https://digitalcommons.chapman.edu/rknowles_correspondence/1034/thumbnail.jp