Error compensation for hybrid-computer solution of linear differential equations

Z-transform technique compensates for digital transport delay and digital-to-analog hold. Method determines best values for compensation constants in multi-step and Taylor series projections. Technique also provides hybrid-calculation error compared to continuous exact solution, plus system stability properties

Fathers' experiences of a mother and baby unit: a qualitative study

Section A presents a literature review of the issues and challenges facing fathers in the postnatal period, in the context of an historical marginalisation of fathers in the study of child development. The review leads to a specific focus on the limited research evidencing the increased risk fathers face to their mental health, when coping with a partner's admission to a Mother and Baby Unit (MBU). Section B Fathers' experience of the joint admission of a partner and child to an MBU has been the subject of limited research, despite initial findings suggesting fathers are at increased risk of postnatal paternal mental health difficulties. This qualitative study aimed to explore the lived experience of fathers in this context, to inform the validity of future research in the area. Interpretative phenomenological analysis was carried out following semi-structured interviews with six fathers in south east England. Five master themes showed that these fathers experienced the onset of their partners' postnatal mental health difficulties as unexpected and traumatic. Fathers needed to acknowledge limits in their ability to help, and the necessity of calling on specialist services. During admission, fathers felt pulled physically and emotionally between managing their own needs, and the needs of their partner and new baby. Themes showing the MBU admission challenged their fathering role and identity were contrasted with the importance fathers placed in treatment needing to be a 'family affair', inclusive and supportive of the father, and mindful of the impacts on the couple relationship. The impact of culture on fathers' adjustment to involvement at the MBU was noteworthy. In conclusion, this research helps understand the importance of including the father where appropriate in a mother's recovery programme, and helping the father define a role alongside the clinical team. The findings of the study validate the efforts of government policy to build effective family focused perinatal services. Section C sets out the journey taken from the ethnographic inception of the research idea, through dilemmas encountered in carrying out the study, to reflections on what was learnt during the process

The ‘connecting children and nature network’: building a collaborative partnership for change

This paper explores the current public and policy interest in ‘children and nature’ from the perspective of a Higher Education Institution. It offers a conceptualisation of concern based on two competing discourses: one of environmental crisis; the other a crisis of childhood. It goes on to argue that rather than being in conflict, the two discourses are actually mutually reinforcing. An implication is that this is an agenda that requires an inter-disciplinary approach requiring those whose primary interest is in the environment to come together with those whose starting point is the child. This conceptual understanding underpins the approach adopted by one UK University in the ‘Connecting Children and Nature Network’. This initiative is an example of how small-scale seed funding can generate significant impacts and is innovative because of its cross-disciplinary support. It is also an example of how Education for Sustainable Development can be embedded through a tripartite model of engagement, teaching and learning, research and knowledge exchange activity. Since its inception further funding has been secured to support the Network and to develop a range of collaborative activities. Although successful, the process of building a partnership has been complex, revealing competing perspectives and agendas. The paper ends with a discussion of some of the lessons learnt and reflects on managing the partnership-building process as an Higher Education Institution

Where are the babies? Engaging under twos with the outdoors

There is a general concern that children are not spending enough time outdoors. The growing number of very young children in the UK and beyond who now spend time in formal day care suggest that it is important to know more about outdoor provision for under twos. This report is based on the first stage of a research project funded by the Froebel Trust which involved reviewing the international research literature on this topic

Courseware in academic library user education: a literature review from the GAELS Joint Electronic Library project

The use of courseware for information skills teaching in academic libraries has been growing for a number of years. The GAELS project was required to create a set of learning materials to support Joint Electronic Library activity at Glasgow and Strathclyde Universities and conducted a literature review of the subject. This review discovered a range of factors common to successful library courseware implementations, such as the need for practitioners to feel a sense of ownership of the medium, a need for courseware customization to local information environments, and an emphasis on training packages for large bodies of undergraduates. However, we also noted underdeveloped aspects worthy of further attention, such as treatment of pedagogic issues in library CAL implementations and use of hypertextual learning materials for more advanced information skills training. We suggest ways of improving library teaching practice and further areas of research

Laser-heated thruster

The development of computer codes for the thrust chamber of a rocket of which the propellant gas is heated by a CW laser beam was investigated. The following results are presented: (1) simplified models of laser heated thrusters for approximate parametric studies and performance mapping; (3) computer programs for thrust chamber design; and (3) shock tube experiment to measure absorption coefficients. Two thrust chamber design programs are outlined: (1) for seeded hydrogen, with both low temperature and high temperature seeds, which absorbs the laser radiation continuously, starting at the inlet gas temperature; and (2) for hydrogen seeded with cesium, in which a laser supported combustion wave stands near the gas inlet, and heats the gas up to a temperature at which the gas can absorb the laser energy

Laser-heated thruster

The development of a computer program for the design of the thrust chamber for a CW laser heated thruster was examined. Hydrodgen was employed as the propellant gas and high temperature absorber. The laser absorption coefficient of the mixture/laser radiation combination is given in temperature and species densities. Radiative and absorptive properties are given to determine radiation from such gas mixtures. A computer code for calculating the axisymmetric channel flow of a gas mixture in chemical equilibrium, and laser energy absorption and convective and radiative heating is described. It is concluded that: (1) small amounts of cesium seed substantially increase the absorption coefficient of hydrogen; (2) cesium is a strong radiator and contributes greatly to radiation of cesium seeded hydrogen; (3) water vapor is a poor absorber; and (4) for 5.3mcm radiation, both H2O/CO and NO/CO seeded hydrogen mixtures are good absorbers

Analytical study of laser supported combustion waves in hydrogen

A one-dimensional energy equation, with constant pressure and area, was used to model the LSC wave. This equation balances convection, conduction, laser energy absorption, radiation energy loss and radiation energy transport. Solutions of this energy equation were obtained to give profiles of temperature and other properties, as well as the relation between laser intensity and mass flux through the wave. The flow through the LSC wave was then conducted through a variable pressure, variable area streamtube to accelerate it to high speed, with the propulsion application in mind. A numerical method for coupling the LSC wave model to the streamtube flow was developed, and a sample calculation was performed. The result shows that 42% of the laser power has been radiated away by the time the gas reaches the throat. It was concluded that in the radially confined flows of interest for propulsion applications, transverse velocities would be less important than in the unconfined flows where air experiments have been conducted

Childhood mental health: an ecological analysis of the effects of neighborhood characteristics

Research on childhood mental illness traditionally examines risk factors most proximal to the child. However, current trends reflect growing interest in how broader contextual factors contribute to psychopathology risk. In this study, we examined neighborhood‐level indicators as potential sources of chronic strain in a sample of 156 mother–child dyads; children were 8 to 12 years old. For most neighborhood indicators, data were collected at the level of census tracts using publicly available data sets. We hypothesized that these indicators would be both associated with greater overall mental health symptoms and specifically predictive of childhood symptoms of depression. We also examined potential mediators (maternal functioning and family cohesion) and moderators (maternal depression). Neighborhood indicators correlated with parents’ ratings of children's overall mental health problems, but did not correlate with children's self‐report of depression symptoms. Maternal functioning mediated neighborhood effects on children's overall mental health problems. Implications and directions for future research are presented.The current work was supported by the following grants from the National Institutes of Health, National Institute of Mental Health MH066077, MH082861, PI: Martha C. Tompson, Ph.D. and MH082861S1, PI: Gail N. Kemp, M.A., M.P.H. (MH066077 - National Institutes of Health, National Institute of Mental Health; MH082861 - National Institutes of Health, National Institute of Mental Health; MH082861S1 - National Institutes of Health, National Institute of Mental Health)Published versio