Re-Examining the Frustrated Homemaker Hypothesis

Multiple Classification Analyses on responses from 946 white women, drawn from the 1972 American National Election Study survey, were used to test the "frustrated homemaker hypothesis" that full-time homemakers are more dissatisfied with their lives than women employed outside the home. The fit between actual and desired roles proved to be a better predictor of personal satisfaction than the traditional dichotomy between homemakers and employed women. Homemakers who had wanted a career were more personally dissatisfied than homemakers who had never wanted a career. The career-oriented homemakers were the ones who expressed greater personal dissatisfaction than employed women. Employed women and career-oriented homemakers were about equally critical of women's collective position in society, while homemakers who had never wanted a career were more accepting of women's status quo. The importance of including evaluations of both personal and collective well-being was shown by the fact that these two domains bore different relationships to employment-homemaker status.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69078/2/10.1177_073088848100800404.pd

Scaling Constraints for Urban Air Mobility Operations: Air Traffic Control, Ground Infrastructure, and Noise

The scalability of the current air traffic control system, the availability of aviation ground infrastructure, and the acceptability of aircraft noise to local communities have been identified as three key operational constraints that may limit the implementation or growth of Urban Air Mobility (UAM) systems. This paper identifies the primary mechanisms through which each constraint emerges to limit the number of UAM operations in an area (i.e. the scale of the service). Technical, ecosystem, or operational factors that influence each of the mechanisms are also identified. Interdependencies between the constraints are shown. Potential approaches to reduce constraint severity through adjustments to the mechanisms are introduced. Finally, an effort is made to characterize the severity of each operational constraint as a function of the density of UAM operations in a region of interest. To this end, a measure of severity is proposed for each constraint. This measure is used to notionally display how the severity of the constraint responds to UAM scaling, and to identify scenarios where efforts to relieve the constraint are most effective. The overall purpose of this paper is to provide an abstraction of the workings of the key UAM operational constraints so that researchers, developers, and practitioners may guide their efforts to mitigation pathways that are most likely to increase achievable UAM system scale

On the Stability of Community Tolerance for Aircraft Noise

Although aircraft noise-induced annoyance prevalence rates vary greatly for similar noise exposure levels in different times and places, some suggest that communities have recently reacted more strongly to aircraft noise than in the past. Others regard claims of greater annoyance over time at similar exposure levels as inconclusive. The current study examined Community Tolerance Level (CTL) values for aircraft noise annoyance studies for temporal trends in 62 studies conducted between 1961 and 2015. The airports studied were classified as "high-rate-of-change" (HRC) and "low-rate-of-change" (LRC) airports. HRC airports experienced large changes in their operational patterns within three years prior to interviewing, or announcement of controversial plans for major changes, and/or extensive public discussions and media focus on operational issues. LRC airports experienced only minor changes in operations and no major noise-related controversies. No significant temporal trend in CTL values was observed over the past 50 years. However, lower tolerance for noise was observed in communities around HRC airports than in communities around LRC airports. Greater numbers of surveys of annoyance at HRC airports in recent years confound differences in CTL values with recency of assessmentacceptedVersio

Arrival Trajectory Optimization for Passenger Aircraft using Genetic Algorithms

This work concentrates on the development of an optimization technique which is capable of minimizing the noise impact of an arriving aircraft by optimizing its flight trajectory. Actions needed from pilots to gradually establish the landing configuration are considered because it is expected that the pilot workload throughout this phase should be remained or even reduced compared with the current standard arrival procedures. Therefore, the conventional point-mass equations of motion are reformulated in such a way that the variations of the aerodynamic performance of the aircraft of different configurations can be easily taken into account. A set of independent state variables are chosen to be parameterized with Bernstein polynomials in order to convert the infinite-dimensional optimal control problem into a finite-dimensional parametric optimization problem. The number of awakenings is selected as the performance index and finally written into a function of the parameters introduced by the parameterization process. Genetic algorithms are employed to optimize these parameters within a search domain in order to minimize the number of awakenings while satisfying all constraints on both state and control variables. A number of numerical examples, for a Boeing 747-400 aircraft arriving at an airport with different population distribution situations, are provided to demonstrate the feasibility and effectiveness of the proposed optimization technique. Without loss of generality, this particular technique is also able to deal with a departing aircraft since most of the models are built into replaceable modules.Control & OperationsAerospace Engineerin