The aerodynamic challenges of SRB recovery

Recovery and reuse of the Space Shuttle solid rocket boosters was baselined to support the primary goal to develop a low cost space transportation system. The recovery system required for the 170,000-lb boosters was for the largest and heaviest object yet to be retrieved from exoatmospheric conditions. State-of-the-art design procedures were ground-ruled and development testing minimized to produce both a reliable and cost effective system. The ability to utilize the inherent drag of the boosters during the initial phase of reentry was a key factor in minimizing the parachute loads, size and weight. A wind tunnel test program was devised to enable the accurate prediction of booster aerodynamic characteristics. Concurrently, wind tunnel, rocket sled and air drop tests were performed to develop and verify the performance of the parachute decelerator subsystem. Aerodynamic problems encountered during the overall recovery system development and the respective solutions are emphasized

Video guidance, landing, and imaging systems

The adaptive potential of video guidance technology for earth orbital and interplanetary missions was explored. The application of video acquisition, pointing, tracking, and navigation technology was considered to three primary missions: planetary landing, earth resources satellite, and spacecraft rendezvous and docking. It was found that an imaging system can be mechanized to provide a spacecraft or satellite with a considerable amount of adaptability with respect to its environment. It also provides a level of autonomy essential to many future missions and enhances their data gathering ability. The feasibility of an autonomous video guidance system capable of observing a planetary surface during terminal descent and selecting the most acceptable landing site was successfully demonstrated in the laboratory. The techniques developed for acquisition, pointing, and tracking show promise for recognizing and tracking coastlines, rivers, and other constituents of interest. Routines were written and checked for rendezvous, docking, and station-keeping functions

Mars Lander Vehicle/Parachute Dynamics

Parachute decelerators used exclusively or in combination with retro rockets have been considered prime candidates for the terminal descent and landing system of a scientifically instrumented Mars lander. The objective of this study is to understand basic relationships between parameters affecting dynamic response of the parachute and capsule and to define those aspects of the system which have a sensitive effect on the design of the lander capsule. Of particular interest is the response of the capsule to wind gusts and to establish the sensitivity to gust onset rates in the VM series of Martian atmospheres. The model used in studying parachute/capsule relationships consists of two bodies, each with three degrees-of-freedom, connected by an elastic riser cable. The total elastic nature of the parachute and shroud lines is simulated by the equivalent elasticity of the riser cable. The parachute and its enclosed and apparent inertia effects are treated in a rigid body sense. Parachute opening phase dynamics are included in the analysis model. Motion of the system is examined in either the pitch or yaw plane with roll motion assumed to be controlled near zero by an attitude control system. Capsule attitude excursions and attitude rates are investigated in detail because of their impact on optical and radar sensors. The ability of a simple rate damping attitude control system to combat capsule oscillations is included in the study. Usually a planetary entry vehicle utilizes a blunt body aeroshell coated with ablative material for the high dynamic pressure, high Mach number portion of the entry trajectory. Once this region has been traversed and Mach number is reduced to approximately 1.6, the parachute decelerator may be deployed. From this point on, the aeroshell serves little usefulness and may complicate the touchdown mechanics. It may be desirable, therefore to jettison the aeroshell as soon as possible after parachute deployment. The ease of accomplishing aeroshell separation while descending on a parachute is evaluated

Molecular characterization of Miraflores peach variety and relatives using SSRs

The definitive version is published in: http://www.sciencedirect.com/science/journal/03044238Some traditional peach varieties, originated from the region of Aragón (Spain), were analysed by SSRs (Simple Sequence Repeats). The aim of this research was to characterize 19 clones related to ‘Miraflores’ variety, with unknown pedigrees, to assess their genetic diversity and to elucidate their possible relationships with 10 traditional peach varieties. Twenty SSR primer pairs with high levels of polymorphism, which have been previously developed for peach, were used in this study. A total of 46 alleles were obtained for all the microsatellites studied, ranging from one to six alleles per locus, with a mean value of 2.3 alleles per locus. Fourteen SSRs were polymorphic in the set of varieties studied and permitted to distinguish 16 different genotypes out of the 30 initially studied, although fourteen ‘Miraflores’ clones showed identical gel profiles. The genetic distance matrix was used to construct Neighbor joining cluster and to perform principal coordinate analysis which allowed the arrangement of all the genotypes according to their genetic relationships. The genetic relationships among these traditional peach varieties, and in particular among ‘Miraflores’ clones are discussed. The obtained results confirm that microsatellite markers are very useful for these purposes.We are thankful to T.N. Zhebentyayeva and G.L. Reighard for helpful comments on the manuscript. This research was funded by CICYT (Comisión Interministerial de Ciencia y Tecnología, AGL2002-04219 and AGL 2005-05533), INIA (Instituto Nacional de Investigación y Tecnología Agraria y Alimentación, RF03-014-C2), Bilateral Spain-France (HF03-273) and DGA (A28, A44) projects and co-funded by the European Regional Development Fund. M. Bouhadida was supported by a fellowship from the AECI (Agencia Española de Cooperación Internacional) of the Spanish Ministry of Foreign Affairs.Peer reviewe

Literacy outcomes for Deaf and Hard of Hearing primary school children: A cohort comparison study

Purpose: This study compared the language and literacy of two cohorts of children with severe-profound hearing loss, recruited 10 years apart, to determine whether outcomes had improved in line with the introduction of newborn hearing screening and access to improved hearing aid technology. Method: Forty-two deaf children, aged 5 -7 years with a mean unaided loss of 102 DB, were assessed on language, reading and phonological skills. Their performance was compared to that of a similar group of 32 deaf children assessed 10 years earlier, and also a group of 40 hearing children of similar single word reading ability. Results: English vocabulary was significantly higher in the new cohort, although it was still below chronological age. Phonological awareness and reading ability had not significantly changed over time. In both cohorts English vocabulary predicted reading but phonological awareness was only a significant predictor for the new cohort. Conclusions: The current results show that vocabulary knowledge of children with severe-profound hearing loss has improved over time but there has not been a commensurate improvement in phonological skills or reading. They suggest that children with severe-profound hearing loss will require continued support to develop robust phonological coding skills to underpin reading

Balloon launched Viking decelerator test program

Four BLDT flights were conducted during the summer of 1972. The purpose of these tests was to qualify the Viking parachute system behind the full-scale Viking entry vehicle over the maximum range of entry conditions anticipated in the Viking '75 soft landing on Mars. A summary of the test series is presented. Test conditions ranged from a Mach number of 2.0 to 0.5 and dynamic pressure from 11.7 to 4.4 psf. This range of conditions covers the uncertainty in entry conditions at Mars due to atmospheric and entry performance uncertainties. Emphasis is placed on parachute performance and simulated Mars entry vehicle motions as influenced by the parachute performance. Conclusions are presented regarding the ability of the parachute to perform within the operational parameters required for a successful soft Martian landing. A list of references which covers all reports in the qualification test program is included

European training requirements for the specialty of medical genetics

The development of European training standards is a major contribution to the improvement of medical training at the European level and one of the core activities of the European Union of Medical Specialists (Union Européenne des Médecins Spécialistes, UEMS). European Training Requirements for the specialty of Medical Genetics (ETR-MG) were first developed and approved in 2017. Here we report the content and objectives of the 2023 revision, carried out by the ETR-MG Working Group and the officers of the UEMS Section of Medical Genetics in close cooperation with the ESHG and the European Board of Medical Genetics (EBMG). New aspects concern an update of the description of the specialty, the integration of the examination for the European Certificate in Medical Genetics and Genomics (ECMGG), a complete restructuring of the syllabus, and the adaption to novel concepts of medical education.</p

Solvation and Protonation of Coumarin 102 in Aqueous Media - a Fluorescence Spectroscopic and Theoretical Study

The ground and excited state protonation of Coumarin 102 (C102), a fluorescent probe applied frequently in heterogeneous systems with an aqueous phase, has been studied in aqueous solutions by spectroscopic experiments and theoretical calculations. For the dissociation constant of the protonated form in the ground state, was obtained from the absorption spectra, for the excited state dissociation constant was obtained from the fluorescence spectra. These values were closely reproduced by theoretical calculations via a thermodynamic cycle – the value of also by calculations via the Förster cycle - using an implicit-explicit solvation model (polarized continuum model + addition of a solvent molecule). The theoretical calculations indicated that (i) in the ground state C102 occurs primarily as a hydrogen bonded water complex, with the oxo group as the binding site, (ii) this hydrogen bond becomes stronger upon excitation; (iii) in the ground state the amino nitrogen atom, in the excited state the carboxy oxygen atom is the protonation site. A comprehensive analysis of fluorescence decay data yielded the values kpr = 3.271010 M-1 s 1 for the rate constants of excited state protonation, and kdpr = 2.78108 s-1 for the rate constant of the reverse process (kpr and kdpr were treated as independent parameters). This, considering the relatively long fluorescence lifetimes of neutral C102 (6.02 ns) and its protonated form (3.06 ns) in aqueous media, means that a quasi-equilibrium state of excited state proton transfer is reached in strongly acidic solutions

Marking their own homework: The pragmatic and moral legitimacy of industry self-regulation

When is industry self-regulation (ISR) a legitimate form of governance? In principle, ISR can serve the interests of participating companies, regulators and other stakeholders. However, in practice, empirical evidence shows that ISR schemes often under-perform, leading to criticism that such schemes are tantamount to firms marking their own homework. In response, this paper explains how current management theory on ISR has failed to separate the pragmatic legitimacy of ISR based on self-interested calculations, from moral legitimacy based on normative approval. The paper traces three families of management theory on ISR and uses these to map the pragmatic and moral legitimacy of ISR schemes. It identifies tensions between the pragmatic and moral legitimacy of ISR schemes, which the current ISR literature does not address, and draws implications for the future theory and practice of ISR