Flight evaluation of a computer aided low-altitude helicopter flight guidance system

The Flight Systems Development branch of the U.S. Army's Avionics Research and Development Activity (AVRADA) and NASA Ames Research Center developed for flight testing a Computer Aided Low-Altitude Helicopter Flight (CALAHF) guidance system. The system includes a trajectory-generation algorithm which uses dynamic programming and a helmet-mounted display (HMD) presentation of a pathway-in-the-sky, a phantom aircraft, and flight-path vector/predictor guidance symbology. The trajectory-generation algorithm uses knowledge of the global mission requirements, a digital terrain map, aircraft performance capabilities, and precision navigation information to determine a trajectory between mission waypoints that seeks valleys to minimize threat exposure. This system was developed and evaluated through extensive use of piloted simulation and has demonstrated a 'pilot centered' concept of automated and integrated navigation and terrain mission planning flight guidance. This system has shown a significant improvement in pilot situational awareness, and mission effectiveness as well as a decrease in training and proficiency time required for a near terrain, nighttime, adverse weather system

Experimental Investigation of a Constant-Velocity Traveling Magnetic Wave Plasma Engine

The previously reported traveling magnetic wave plasma engine has been redesigned to reduce the high heat loss to the tube walls downstream of the last magnetic-field coil. The present configuration uses a 3-inch-diameter pyrex tube flared out to a 6-inch diameter immediately downstream of the last magnetic-field coil. This configuration has been studied to determine the effects of flared-tube geometry, molecular weight of the propellant, engine length, and use of a ferrite core on the engine performance. Argon and xenon gases were used as propellants. Two engine lengths were tested. One engine was nominally 1-magnetic-wavelength long (4 coils) and the other nominally 2 1/2-magnetic wavelengths long (10 coils). The magnetic wave speed for both of these lengths corresponds to a specific impulse of 4750 seconds. The maximum kinetic efficiency of the 4-coil engine was 10 percent at a specific impulse of 3200 seconds using argon gas and 22.5 percent at 4200 seconds using xenon gas as the propellant

Some operating features of a 100,000-volt transmission

A Thesis presented to the faculty of the graduate school of the University of Kansas for the Degree of Electrical Engineer

The Rhetorical Strategies of Pregnancy Support Centers Including the Visual Rhetoric of Fetal Ultrasound Technology

This study examined the rhetorical strategies, including verbal and visual rhetoric, of pregnancy support centers that provide clients with fetal ultrasounds to persuade those who may be considering abortion as a means of resolving their unplanned pregnancy to carry to term. Qualitative data were gathered from 12 interviews of directors and ultrasound personnel from 7 states as well as from television advertisements and printed material. Eighteen research questions investigating the rhetorical transactions between centers and clients were answered. Rhetorical analyses were performed on the verbal and visual messages used in client interactions. The grounded theory approach of inquiry resulted in the discovery of 10 major themes. First, centers offer holistic Christian ministry to clients. Second, centers provide professional health services. Third, a quest for uncertainty reduction and information brings clients to the centers. Fourth, centers maintain safe supportive environments. Fifth, personnel are trained to demonstrate sensitivity in sharing information. Sixth, staff exercise care in their deliberate choice of terms. Seventh, members recognize the importance of interpersonal communication in building relationships with and mentoring clients. Eighth, centers use persuasive arguments and artifacts. Ninth, ultrasound serves to reify the pregnancy for clients. Tenth, empowering clients to make their own decisions is a center goal. A rhetorical critique was performed using three approaches. First, the rhetorical functions communicated by the visual artifacts were explored. Second, the individual elements of the visuals were examined for persuasive potential. Third, the possibility that the visual of the ultrasound image fills the eye of the beholder with a single dominant meaning was considered. The conclusion is that the apparent persuasive success of the ultrasound can be partially explained by the client\u27s recognition of baby schema characteristics present in the fetus, recognition of the fetal heartbeat, and recognition of the beating heart as a symbol of life. The persuasive potential of the fetal position and fetal movement were also discussed. The role of storytelling was examined. The possibility of client self-persuasion was also evaluated

Study of the assignment and its improvement

Thesis (Ed.M.)--Boston University, 1934. This item was digitized by the Internet Archive

Prison higher education in Massachusetts : an exploratory cultural analysis.

The focus of this inquiry is upon higher education programs that offer post-secondary educational opportunities to men and women incarcerated in correctional facilities operated by the Massachusetts Department of Correction. The inquiry is exploratory, and both descriptive and theoretical. Its purpose was to generate a preliminary social facts description of prison higher education and a theoretical lens capable of guiding an examination of higher education as a mechanism for status reformation among prisoners. Because cultural analyses seek to make explicit social structures that make meaning possible, the inquiry design incorporates both deductive and empirical methods. Prison higher education was defined as a special case in the more general expansion of higher education. Higher education was viewed as a system of contexts that reproduce a stratified society by regulating the social value of participation. The efficacy of prison higher education as a status transformation mechanism was seen to be delimited its location within this system of contexts. The directors of six (6) prison higher education programs in Massachusetts participated in the empirical component of this inquiry by completing a questionnaire that sought information about personal backgrounds, program characteristics, and perceptions regarding the intersection of higher education and incarceration. The empirical findings were reported in Appendix A and comprise a preliminary description of prison higher education in Massachusetts. That description facilitated continuation of the theoretical discussion regarding the concept of prison higher education. It was concluded that higher education\u27s historical pattern of expansion through the creation of educational forms and contexts that roughly mirror social expectations about participants lends strong support to the proposition that it became possible to educate prisoners precisely because some of those forms and contexts are no longer wholly in conflict with social expectations of what it means to be a prisoner. Support was also gained for the tentative propositions that prison higher education in Massachusetts is an element of mass education, that it may be evolving into an educational specialized context within mass education, that participation in programs of prison higher education is not likely to result in credible status transformations within or beyond the structure of confinement

Advanced turbulence modeling for industrial flows

This dissertation deals with the development of an improved two-equation turbulence model and its application to various flows. Six different conventional turbulence models were initially tested for predicting the flow inside of an unbaffled stirred tank reactor (STR), and the results are compared with experimental LDV data. Each of the models use low Reynolds number corrections. Results indicate that the radial velocity component in the impeller discharge region is overpredicted by each of the models. The tangential velocity component in the impeller discharge region is predicted well by the models, but is underpredicted near the shaft. The low Reynolds number k-ε model is the only model which produces reasonable kinetic energy predictions in the impeller discharge region. The model predictions are generally unsatisfactory and produce varying results, which are largely attributed to the difference in the formulation of the low Reynolds number corrections for each model. Based on these results a new model has been developed which eliminates the need for low Reynolds number corrections and has been demonstrated to produce improved results for various flows compared with the conventional models. The new model, called the v2f-kω model, is developed based on the elliptic relaxation approach of Durbin and is a variant of Durbin\u27s v2f-kε model. The new model is shown to be superior to all other models on a number of benchmark problems including the backstep, two-dimensional cavity, coaxial jet and jet in a crossflow. The new model is therefore proposed as a superior alternative from both computational effectiveness and accuracy viewpoints

Feature preserving smoothing of 3D surface scans

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, February 2004.Includes bibliographical references (p. 63-70).With the increasing use of geometry scanners to create 3D models, there is a rising need for effective denoising of data captured with these devices. This thesis presents new methods for smoothing scanned data, based on extensions of the bilateral filter to 3D. The bilateral filter is a non-linear, edge-preserving image filter; its extension to 3D leads to an efficient, feature preserving filter for a wide class of surface representations, including points and "polygon soups."by Thouis Raymond Jones.S.M

Seasonal apiary management for Missouri

Flernoy Jones (Department of Entomology, College of Agriculture), Raymond Nabors (Area Entomology Specialist, Delta Center)New 2/87/6