3,811 research outputs found
The Calibrations of Space Shuttle Main Engines High Pressure Transducers
Previously, high pressure transducers that were used on the Space Shuttles Main Engine (SSME) exhibited a severe drift after being tested on the SSME. The Experimental Testing Technology Division (ETTD) designed some new transducers that would not exhibit a severe drift over a short period of time. These transducers were calibrated at the Test Bed at Marshall Space Flight Center (MSFC). After the high pressure transducers were calibrated, the transducers were placed on the SSME and fired. The transducers were then sent to the NASA LaRC to be recalibrated. The main objectives of the recalibrations was to make sure that the transducers possessed the same qualities as they did before they were fired on the SSME. Other objectives of the project were to determine the stability of the transducers and to determine whether the transducers exhibited a severe drift
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Measuring children and young people's wellbeing in the school context
Although being rooted in the work of ancient Greek philosophers, contemporary research on wellbeing is a relatively new phenomenon. As a term in the literature, wellbeing is often used interchangeably with others, such as happiness, flourishing, enjoying a good life, and life satisfaction. Furthermore the wellbeing of school-aged children is only beginning to be explored with increasing recognition that research conducted on adults cannot be uncritically applied to children and young people. This paper aims to address some of the complexities in conceptualising, and hence assessing, children and young people’s wellbeing by drawing on a recently completed study examining the role of creative initiatives in fostering wellbeing. The new instrument that was developed to capture children and young people’s perceptions of their wellbeing in school is outlined. Data are presented from a survey of 5170 students from 20 primary and 20 secondary schools across England that identify four dimensions of wellbeing. Differences in self-reported wellbeing relating to age, gender and type of school attended (Creative Partnerships versus other schools) are explored. The implications of these findings, particularly differences related to type of school attended given the focus of this special edition, are considered.This is the author accepted manuscript. The final version is available from Taylor & Francis via http://dx.doi.org/10.1080/0305764X.2014.88965
On the locus formed by the maximum heights of projectile motion with air resistance
We present an analysis on the geometrical place formed by the set of maxima
of the trajectories of a projectile launched in a media with linear drag. Such
a place, the locus of apexes, is written in term of the Lambert function in
polar coordinates, confirming the special role played by this function in the
problem. In order to characterize the locus, a study of its curvature is
presented in two parameterizations, in terms of the launch angle and in the
polar one. The angles of maximum curvature are compared with other important
angles in the projectile problem. As an addendum, we find that the synchronous
curve in this problem is a circle as in the drag-free case.Comment: 7 pages, 6 color eps figures. Synchronous curve added. Typos and
style corrected
Indian River Lagoon surface water improvement and management (SWIM) plan, 2002 update.
In recognition of the need to place additional emphasis on the restoration, protection, and management of the surface water resources of the state, the Florida Legislature, through the Surface Water Improvement and Management (SWIM) Act of 1987, directed the state’s water management districts to “design and implement plans and programs for the improvement and management of surface water” (Section 373.451, Florida Statutes [FS]). The SWIM legislation requires the water management districts to protect the ecological, aesthetic, recreational, and economic value of the state’s surface water bodies, keeping in mind that water quality degradation is frequently caused by point and nonpoint source pollution and that degraded water quality can cause both direct and indirect losses of aquatic habitats.
This 2002 update is the second update of the Indian River Lagoon SWIM Plan. This 2002 plan update includes a status report on the state of the Lagoon, a summary of progress on projects undertaken since the last update, and recommendations for future projects and other actions over the next 5 years. (262pp.
The Experiences of Late-diagnosed Women with Autism Spectrum Conditions: An Investigation of the Female Autism Phenotype
We used Framework Analysis to investigate the female autism phenotype and its impact upon the under-recognition of autism spectrum conditions (ASC) in girls and women. Fourteen women with ASC (aged 22-30Â years) diagnosed in late adolescence or adulthood gave in-depth accounts of: 'pretending to be normal'; of how their gender led various professionals to miss their ASC; and of conflicts between ASC and a traditional feminine identity. Experiences of sexual abuse were widespread in this sample, partially reflecting specific vulnerabilities from being a female with undiagnosed ASC. Training would improve teachers' and clinicians' recognition of ASC in females, so that timely identification can mitigate risks and promote wellbeing of girls and women on the autism spectrum
Modeling the Raven SCS-700 Chemical Injection System with Carrier Control with Sprayer Simulation
Mathematical models of the chemical and carrier control sub-systems of the Raven SCS-700 chemical injection system were developed. The step responses of both control sub-systems were predictable using the models. From this process of model development, it was observed that the voltage saturation effect limited the response speed of the carrier valve motor and the resulting speed at which changes could be made to the carrier flow rate. The rate at which flow rate measurements were available limited the extent to which valve motor speed could be increased without causing instability. The performance of three different types of sprayers was simulated using these models. Simulations were performed with and without carrier control. Sprayers using carrier control misapplied to smaller areas than those without carrier control. Differences between the response of the chemical and carrier sub-system controllers produced concentration variations that contributed to application error. These errors, however, were small relative to the errors caused by response times of both systems and the ground speed sampling rate
A Cross-Cultural Study of Vocational Identity: Does a College Education Mean the Same for All Persisters?
This item is copyright by Johns Hopkins University Press.No abstract is available for this item
Coordination Implications of Software Coupling in Open Source Projects
The effect of software coupling on the quality of software has been studied quite widely since the seminal paper on software modularity by Parnas [1]. However, the effect of the increase in software coupling on the coordination of the developers has not been researched as much. In commercial software development environments there normally are coordination mechanisms in place to manage the coordination requirements due to software dependencies. But, in the case of Open Source software such coordination mechanisms are harder to implement, as the developers tend to rely solely on electronic means of communication. Hence, an understanding of the changing coordination requirements is essential to the management of an Open Source project. In this paper we study the effect of changes in software coupling on the coordination requirements in a case study of a popular Open Source project called JBoss
Flex, an X-linked female-lethal mutation in Drosophila melanogaster controls the expression of sex-lethal
The Sex-lethal (Sxl) gene is required in Drosophila females for sexual differentiation of the soma, for gem cell differentiation and dosage compensation. We have isolated three new alleles of female-lethal-on-X (flex), an X-linked female-lethal mutation and have characterized its function in sex determination. SXL protein is missing in flex/flex embryos, however transcription from both Sxl(Pe), the early Sxl promoter and Sxl(Pm), the late maintenance promoter, is normal in flex homozygotes. In flex/flex embryos, Sxl mRNA is spliced in the male mode. Analysis of flex germline clones shows that it also functions in oogenesis, but in contrast to Sxl mutants that show an early arrest tumorous phenotype, flex mutant egg chambers develop to stage 10. In flex ovarian clones, Sxl RNA is also spliced in the male form. Hence, flex is a sex-specific regulator of Sxl functioning in both the soma and the germline. Genetic interaction studies show that flex does not enhance female lethality of Sxl loss-of-function alleles but it rescues the male-specific lethality of both of the gain-of-function Sxl mutations, Sxl(M1)and Sxl(M4.) In contrast to mutations in splicing regulators of Sxl, the female lethality of flex is not rescued by either Sxl(M1)or Sxl(M4). Based on these observations, we propose that flex regulates Sxl at a post-splicing stage and regulates either its translation or the stability of the SXL protein
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