Application study of filamentary composites in a commercial jet aircraft fuselage

A study of applications of filamentary composite materials to aircraft fuselage structure was performed. General design criteria were established and material studies conducted using the 727-200 forebody as the primary structural component. Three design approaches to the use of composites were investigated: uniaxial reinforcement of metal structure, uniaxial and biaxial reinforcement of metal structure, and an all-composite design. Materials application studies for all three concepts were conducted on fuselage shell panels, keel beam, floor beams, floor panels, body frames, fail-safe straps, and window frames. Cost benefit studies were conducted and developmental program costs estimated. On the basis of weight savings, cost effectiveness, developmental program costs, and potential for early application on commercial aircraft, the unaxial design is recommended for a 5-year flight service evaluation program

Supporting disabled parents' involvement in their children's education. Good practice guidance for schools

In this guidance you will find the voices of a range of disabled parents describing how good practice in schools has helped them to be involved in their children's education. The guidance is based on the findings of a research project. It is intended for people working in schools, especially heads and teachers seeking to improve parental participation and inclusion. Education policy makers and Inspectorates may find it helpful for informing their reviews of policy and practice. It may also be of interest to disabled parents and the disability voluntary sector. The document contains information about current UK policies on parental involvement and describes the research project which investigated the perceptions of disabled parents. It looks at five different aspects of parental involvement, giving examples of good practice and highlighting suggestions as these emerged from the research project. Key points are summarised in the conclusion, while the appendices include useful resources and contacts

Quantum paramagnetic ground states on the honeycomb lattice and field-induced transition to N\'eel order

Motivated by recent experiments on Bi$_3$Mn$_4$O$_{12}$(NO$_3$), and a broader interest arising from numerical work on the honeycomb lattice Hubbard model, we have studied the effect of a magnetic field on honeycomb lattice spin models with quantum paramagnetic ground states. For a model with frustrating second-neighbor exchange, $J_2$, we use a Lindemann-like criterion within spin wave theory to show that N\'eel order melts beyond a critical $J_2$. The critical $J_2$ increases with a magnetic field, implying the existence of a field-induced paramagnet-N\'eel transition over a range of $J_2$. We also study bilayer model using a spin-$S$ generalization of bond operator mean field theory. We show that there is a N\'eel-dimer transition for various spin values with increasing bilayer coupling, and that the resulting interlayer dimer state undergoes a field induced transition into a state with transverse N\'eel order. Finally, we study a spin-3/2 model which interpolates between the Heisenberg model and the Affleck-Kennedy-Lieb-Tasaki (AKLT) parent Hamiltonian. Using exact diagonalization, we compute the fidelity susceptibility to locate the Neel-AKLT quantum critical point, obtain the spin gap of the AKLT parent Hamiltonian, and argue that AKLT state also undergoes field-induced Neel ordering.Comment: 8 pages, revised longer version of arXiv:1012.0316. Corrected factor of 2 error in Eq.[16], replotted Fig.[4] and revised the critical $J_c/J_1$ needed to stabilize interlayer dimer state. We thank S. V. Isakov for discussions which uncovered this erro

Missing Pieces in the Service Learning Puzzle

The increasing popularity in the schools for sponsoring service learning or community service reflects the grave concern that more has to be done to teach youth to participate in a democratic society. The declining voting turnout and the reported low involvement of adults in community groups are often cited as a need for the schools to counter the current apathy and cynicism about government and political leaders. Whether there really is a decline in civic involvement is open to question but the national debate on promoting civic education and social responsibility is reflected in state and local communities requiring students\u27 participation in community service

Ecological considerations for possible Martian biota

Current climatic and geological evidence suggests that, like early Earth, conditions on ancient Mars may also have been favorable for the origin and evolution of life. The primordial atmospheres of the two planets were quite similar, composed primarily of CO2, N2, and water vapor at a total atmospheric pressure of approximately 1 bar. Each of these gases are important for the evolution of biological systems. With the exception of nitrogen, there seems to have been a sufficient supply of the biogenic elements C, H, O, P, and S (CHOPS) on early Mars for life to have evolved. It was postulated that primordial Mars contained only 18 mb of nitrogen in the form of N2 given that only fixed nitrogen is utilized by living systems. Laboratory tests performed at a total pressure of 1 bar and various partial pressures of dinitrogen (pN2 1-780 mb) show that nitrogen fixing organisms grow at pN2's of 18 mb or less, although the biomass and growth rates are decreased. The calcualted in vivo Km's ranged from 46 mb to 130 mb. If organisms adapted on Earth to a pH2 of 780 mb are capable of growing at these low partial pressures, it is conceivable that nitrogen was not the limiting factor in the evolution of life on early Mars

Contraception: Securing Feminism’s Promise

This paper traces the history of attempts to restrict contraception, the legal events securing widespread access to contraception and their importance to a generation of college-aged women, the short-lived nature of the consensus that produced them, and the potential of the issue to serve as a rallying point for a revitalized feminism. It explores the hypocrisy of a system that, whatever its values, makes reproductive autonomy readily available for the affluent and the sophisticated and increasingly beyond the reach of the most vulnerable. Finally, it considers the potential of contraception as a reframing device, capable of exposing the hypocrisy of family values advocates whose policies disproportionately hurt the most vulnerable

Family Classes: Rethinking Contraceptive Choice

The political attention paid to moral values - in the context of the high profile fights over abortion, homosexuality, and abstinence education - has developed over the past quarter century in ideological terms as though race and class no longer existed. In fact, the changing understandings that attend family formation reflect a long term shift in the pathways to middle class life which has created a new technocratic elite - an elite that invests heavily in both men and women’s advanced degrees, and has remade family life to its advantage. The success of the new model, which we call the “blue family paradigm,” and the sexual revolution at its core undermines what had once been consensus support for traditional values (which we will call “the red family paradigm”), and for the structure of family life following from abstinence to courtship to marriage. The result of the tensions between these family ideals has been a moral backlash. In this Article, we highlight the tensions between the two family models, focusing on contraception, and critique the class-based nature of the results. We argue that the politicization of family issues has produced its own “vicious cycle” of moral concern, draconian changes that disproportionately affect the poorest and most vulnerable Americans, and a new round of moral panic justifying further punitive measures, as the initial restrictions (such as closing abortion clinics and slashing family planning funds) make matters worse. We conclude that the “culture wars” are very much about class, and yet they are framed as a fight between two relatively privileged groups, in which class implications of the struggle disappear from sight. This Article argues that only by making these class implications visible - for low income, middle class, and wealthy individuals - can we design more effective interventions that can break the cycle

The Biological Basis of Commitment: Does One Size Fit All?

Understanding the biological roots of intimate behavior is a complex undertaking that involves the integration of evolutionary biology, evolutionary psychology, neuroscience, anthropology and sociology. Evolutionary biology describes theories that explain the persistence of certain types of behavior in terms of presumed evolutionary pressures or advantages, focusing on the human mind. Evolutionary biologists assume that behavior that maximizes the presence of associated genes in the next generation is the behavior most likely to persist. In this paper, we take the growing insights that arise from the study of the biology of attachment to frame the emerging policy choices underlying the governance of adult relationships. We have chosen to focus on the idea of commitment because we see two developments operating in tandem: the biological understanding of attachment has been expanding exponentially at a time of reexamination of the importance of long-term family stability. We believe that putting the two together--integrating biological understandings with sociology - will lead to the conclusions that the tendency to form pair-bonds is a deeply ingrained part of the species, lifelong fidelity cannot be expected on a widespread basis absent substantial coercion, and long term partnership is a compromise that children win. These conclusions, however, will always leave some questions unanswered so that they can do no more than frame the unfolding policy debates. The question of what policy choices work - and at what price - can never be answered by biology alone. A better understanding of the new scientific insights underscores the conclusion that the determination of what is natural produces complex and varied answers, and the most natural of human tendencies is the desire to reorder human society. Accordingly, in light of the developing understandings of human pair-bonds from both the biological and sociological perspectives, we suggest various strategies that support long-term commitment between adults