Transportation Systems Analyses (TSA): Highly Reusable Space Transportation (HRST). A preliminary programmatic assessment

This report overviews the strategic implications of the Highly Reusable Space Transportation (HRST) program. The analysis postulates the anticipated HRST market (window is 2006-30, with a 2015 focus). Next the analysis speculates on market 'price of entry' for several potential markets. HRST is envisioned as a NASA overlay to either the STS modernization or the on-going RLV initiative. Three NASA options are reviewed. An example HRST program (MagLifter + RBCC RLV) is assessed in terms of financial/political issues. The merits of HRST-vs-RLV are briefly examined. Finally, a Small Launch Vehicle (SLV) HRST application is reviewed

Settled Cryogenic Propellant Transfer

Cryogenic propellant transfer can significantly benefit NASA s space exploration initiative. LMSSC parametric studies indicate that "Topping off" the Earth Departure Stage (EDS) in LEO with approx.20 mT of additional propellant using cryogenic propellant transfer increases the lunar delivered payload by 5 mT. Filling the EDS to capacity in LEO with 78 mT of propellants increases the delivered payload by 20 mT. Cryogenic propellant transfer is directly extensible to Mars exploration in that it provides propellant for the Mars Earth Departure stage and in-situ propellant utilization at Mars. To enable the significant performance increase provided by cryogenic propellant transfer, the reliability and robustness of the transfer process must be guaranteed. By utilizing low vehicle acceleration during the cryogenic transfer the operation is significantly simplified and enables the maximum use of existing, reliable, mature upper stage cryogenic-fluid-management (CFM) techniques. Due to settling, large-scale propellant transfer becomes an engineering effort, and not the technology development endeavor required with zero-gravity propellant transfer. The following key CFM technologies are all currently implemented by settling on both the Centaur and Delta IV upper stages: propellant acquisition, hardware chilldown, pressure control, and mass gauging. The key remaining technology, autonomous rendezvous and docking, is already in use by the Russians, and must be perfected for NASA whether the use of propellant transfer is utilized or not

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Direitos humanos internacionais: conseqüências não intencionais da guerra contra o terrorismo International human rights: unintended consequences of the war on terrorism

O artigo trata da política externa norte-americana para direitos humanos no pós-11 de setembro. O argumento central é o de que as preocupações humanitárias foram obscurecidas pelo recrudescimento das questões de segurança na agenda política norte-americana desde os ataques terroristas em 2001. Ademais, o próprio conceito de segurança foi alterado. A ideologização provocada pela guerra antiterrorismo fez com que interesses em segurança passassem a ser concorrentes dos interesses em direitos humanos, revertendo o processo de mudança da política externa norte-americana iniciado no pós-Guerra Fria. A demonização do inimigo e a adoção de postura política cada vez mais unilateral por parte de Washington favorecem uma visão de "segurança nacional" que deixa pouco (ou nenhum) espaço para os direitos humanos internacionais. Contudo, as conseqüências resultantes da mudança na política externa americana podem ser consideradas, em larga medida, não intencionais, o que abriria espaço para uma possível ampliação da dimensão humana nas questões de segurança, desde que alterada também a conjuntura internacional.<br>The article aims at discussing US foreign policy regarding international human rights after September, 11th. The main argument is that humanitarian concerns have been eclipsed by the re-inflation of security concerns in US foreign policy agenda since the terrorist attacks in 2001. Besides, there have been changes in the understanding of security. The definition of security in more ideological terms caused by the war on terror has created a competitive relation between human rights and security interests, retreating the process of change in US foreign policy that had begun after the end of the Cold War. The demonization of enemies and Washington's tendency towards unilateralism favor a vision of "national security" that leaves little (or no) space for international human rights. However, the consequences of the recent changes in US foreign policy are, to a large extent, unintended. This could allow for a potential increase in the human dimension of security concerns, as long as the international scenario changes in the forthcoming years