Optimum design of high speed prop rotors including the coupling of performance, aeroelastic stability and structures

An optimization procedure is developed for the design of high speed prop-rotors to be used in civil tiltrotor applications. The goal is to couple aerodynamic performance, aeroelastic stability, and structural design requirements inside a closed-loop optimization procedure. The objective is to minimize the gross weight and maximize the propulsive efficiency in high speed cruise. Constraints are imposed on the rotor aeroelastic stability in both hover and cruise and rotor figure of merit in hover. Both structural and aerodynamic design variables are used

Manitoba Women and Higher Education: Momentum to Stay the Course

Her education is the same as that of a man ... she is able to unfold and exercise her mental powers and faculties. She chooses her occupation in such a way as corresponds with her wishes, inclinations and natural abilities, and she works under conditions identical with man\u27s. Even if engaged as a practical working woman on some field or other, at other times of the day she may be educator, teacher, or nurse, as yet others she may exercise herself in art, or cultivate some branch of science, and yet others may be filling some demonstrative function. She joins in studies, enjoyments or social intercourse with either her sisters or with men, as she may please or occasion may serve. (Bebel cited in Kinnear, 1995, p. 5

Lifetime Earnings Variability and Retirement Wealth

This paper explores how earnings variability is related to retirement wealth. Past research has demonstrated that the average American household on the verge of retirement would need to save substantially more, in order to preserve consumption flows in old age. While several socioeconomic factors have been examined that might explain such problems, prior studies have not assessed the role of earnings variability over the lifetime as a potential explanation for poor retirement prospects. Thus two workers having identical levels of average lifetime earnings might have had very different patterns of earnings variability over their lifetimes. Such differences could translate into quite different retirement wealth outcomes. This paper evaluates the effect of earnings variability on retirement wealth using information supplied by respondents to the Health and Retirement Study (HRS). This is a rich and nationally representative dataset on Americans on the verge of retirement, with responses linked to administrative records from the Social Security Administration. Our research illuminates the key links between lifetime earnings variability and retirement wealth.

Supporting the Visual-Cognitive Sciences by Exploring the Application of Photographic Composition to Visual Scene Displays

AAC systems may be accessed via techniques such as touch, eye gaze and switch scanning, which are then translated into communication output. Traditionally, aided AAC displays utilize a grid layout, arranging communication items in a decontextualized manner. In contrast, visual scene displays (VSDs) utilize context rich images (e.g., photographs) that depict events and activities, presenting communication items in a contextualized manner (e.g., a toy in a toy chest; Wilkinson, Light, & Drager, 2012). Recent research focusing on principles of the visual-cognitive sciences has found that even small changes in how we present communication items in a grid or VSD format may positively influence communication outcomes (Light, Wilkinson, Thiessen, Beukelman, & Fager, 2019). For instance, to support access to VSDs, research in the visual-cognitive sciences has identified that including meaningful interactions and human figures may engage individuals in scene content and promote VSD-based AAC success. AAC has a history of benefitting from bringing the perspectives of outside disciplines into conversations related to innovation and service delivery. Although digital photographs are easier than ever to obtain, there is still room for consideration of what makes a “good” photograph and capturing contextually rich photographs can make an enormous difference in the communication interactions these images support. Principles of photographic and art composition may support findings from the visual-cognitive sciences by limiting scene complexity through increased image structure and brining the viewers’ attention to key scene elements (e.g., Peterson et al., 2003) that may be targeted during direct selection or scanning-based paradigms. Therefore, compositional factors may help ensure that an individual is not being distracted or possibly ‘pulled out’ of the scene during VSD viewing. Further, the use of compositional strategies in VSD design may provide avenues for the sorting and categorization of communication content on the AAC device, by allowing image sorting software to identify well composed images that are most likely to support communication success and social participation

Problems in using social work records in assessing change

Thesis (M.S.)--Boston Universit

Estimating soil erosion for conservation planning

"Soil type, crop rotation, r11infall, tillage practices, topography and conservation practices used are a few of the factors which determine the potential for soil erosion at specific sites within fields. Over the years, several equations have been used to estimate erosion for various agricultural conservation planning programs. The most effective tool was developed by W. H. Wischmeier . and D. D. Smith of the Agricultural Research Service/ USDA and is called the Universal Soil Loss Equation (USLE). The USLE was based on more than 10,000 plotyears of soil erosion research conducted at 49 locations in the U.S. The equation has proven to be effective for evaluating the impact of such factors as crop rotation, tillage systems, vegetative cover, contouring and terraces on the potential for erosion control."--First page.John R. McCarthy (Soil Conservation Service), Donald L. Pfost (Agricultural Engineering Department), Nyle Wollenhaupt (Agronomy Department

Conservation tillage and residue management to reduce soil erosion

"Crop-residue management through conservation tillage is one of the best and most cost-effective ways to reduce soil erosion. Conservation tillage and residue management may reduce machinery expenses and save soil, labor, fuel and money. Crop residues uniformly distributed over the soil surface will significantly reduce soil losses over an entire field. On terraced land, the resultant reduction in soil losses due to this residue cover can greatly reduce the cost of terrace maintenance."--First page.John R. McCarthy (Soil Conservation Service), Donald L. Pfost (Agricultural Engineering), Nyle C. Wollenhaupt (Agronomy Department

Forever Young: High Chromospheric Activity in M subdwarfs

We present spectroscopic observations of two halo M subdwarfs which have H alpha emission lines. We show that in both cases close companions are the most likely cause of the chromospheric activity in these old, metal-poor stars. We argue that Gl 781 A's unseen companion is most likely a cool helium white dwarf. Gl 455 is a near-equal-mass M subdwarf (sdM) system. Gl 781 A is rapidly rotating with v sin i = 30 km/s. The properties of the chromospheres and X-ray coronae of these systems are compared to M dwarfs with emission (dMe). The X-ray hardness ratios and optical chromospheric lines emission ratios are consistent with those seen in dMe stars. Comparison to active near-solar metallicity stars indicates that despite their low metallicity ([m/H] = -1/2), the sdMe stars are roughly as active in both X-rays and chromospheric emission. Measured by L_X/L_bol, the activity level of Gl 781 A is no more than a factor of 2.5 subluminous with respect to near-solar metallicity stars.Comment: 16 pages including 1 figure, AASTeX, to appear in May 1998 A.