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In this paper, a state-of-the-art Artificial Intelligence (AI) technique is used for a precipitation hardening of Ni-based alloy to predict more flexible non-isothermal aging (NIA) and to examine the possible routes for the enhancement in strength that may be practically achieved. Additionally, AI is used to integrate with Materials Integration by Network Technology, which is a computational workflow utilized to model the microstructure evolution and evaluate the 0.2% proof stress for isothermal aging and NIA. As a result, it is possible to find enhanced 0.2% proof stress for NIA for a fixed time of 10 min compared to the isothermal aging benchmark. The entire search space for aging scheduling was ~ 3 billion. Out of 1620 NIA schedules, we succeeded in designing the 110 NIA schedules that outperformed the isothermal aging benchmark. Interestingly, it is found that early-stage high-temperature aging for a shorter time increases the γ′ precipitate size up to the critical size and later aging at lower temperature increases the γ′ fraction with no anomalous change in γ′ size. Therefore, employing this essence from AI, we designed an optimum aging route in which we attained an outperformed 0.2% proof stress to AI-designed NIA routes. [ABSTRACT FROM AUTHOR]

Mounting ambitions and capabilities for public and private, non-government sector crewed space exploration bring with them an increasingly diverse set of space travelers, raising new and nontrivial ethical, legal, and medical policy and practice concerns which are still relatively underexplored. In this piece, we lay out several pressing issues related to ethical considerations for selecting space travelers and conducting human subject research on them, especially in the context of non-governmental and commercial/private space operations. New and dynamically changing opportunities for commercial/private and civilian spaceflight raise the need for an examination of how to ethically guide space industry and community. This Perspective explores such considerations with respect to space traveler selection and human subject research. [ABSTRACT FROM AUTHOR]

It is widely acknowledged that NATO has multiple rationales. What is more contestable is the view that the burgeoning complexity of the security environment feeds these rationales and that NATO may not be able to cope. If each rationale is like a personality, then NATO's multiple personalities have a corrosive effect on the Alliance since they prevent it from setting consistent goals and pursuing them. The prescribed cure is a clarified personality that emphasises one rationale at the expense of others. This paper questions the metaphor behind this debate. NATO's multiple rationales are built into the Alliance, we argue, and a better metaphor may be NATO as a congress whose members are independent yet tied to an overarching political project. Such a congress will never be unitary, but it can at times make decisions. Sometimes decision-making will require grand and thus elusive bargains; sometimes it can be moved from formal committees to backroom caucuses that eschew big questions of rationale and instead focus on problem-solving. In any case, congresses can cope with persistent, competing preference orderings and divergent resource bases among constituent states. Where the split personality analogy leads to the collapse of NATO as a coherent actor, the congress metaphor affords better notional explanations for what we actually observe, a messy, raucous alliance that muddles through from Kabul to Earth orbit.1 An earlier version of this article was presented at the International Studies Association Annual Conference, New Orleans, LA, February 17–20, 2010. This academic work does not represent the official views of the United States Government or the United States Air Force. The authors acknowledge the Danish Social Science Research Council (grant 09-064015/FSE) and the Norwegian Institute for Defence Studies for funding research into the Atlantic Alliance that enabled the writing of this paper. For support and comments, we also thank the Eisenhower Center for Space and Defense Studies at the United States Air Force Academy, Eisenhower Center director Roger Harrison, Sean Crean, Mick Gleason, and Pete Hays. The opinions herein and any factual errors are strictly our own. [ABSTRACT FROM AUTHOR]

Severe geomagnetic storms appear to be ordered by the solar cycle in a number of ways. They occur more frequently close to solar maximum and the declining phase, are more common in larger solar cycles, and show different patterns of occurrence in odd- and even-numbered solar cycles. Our knowledge of the most extreme space-weather events, however, comes from spikes in cosmogenic-isotope (14C, 10Be, and 36Cl) records that are attributed to significantly larger solar energetic-particle (SEP) events than have been observed during the space age. Despite both storms and SEPs being driven by solar-eruptive phenomena, the event-by-event correspondence between extreme storms and extreme SEPs is low. Thus, it should not be assumed a priori that the solar-cycle patterns found for storms also hold for SEPs and the cosmogenic-isotope events. In this study, we investigate the solar-cycle trends in the timing and magnitude of the 67 SEP ground-level enhancements (GLEs) recorded by neutron monitors since the mid-1950s. Using a number of models of GLE-occurrence probability, we show that GLEs are around a factor of four more likely around solar maximum than around solar minimum, and that they preferentially occur earlier in even-numbered solar cycles than in odd-numbered cycles. There are insufficient data to conclusively determine whether larger solar cycles produce more GLEs. Implications for putative space-weather events in the cosmogenic-isotope records are discussed. We find that GLEs tend to cluster within a few tens of days, likely due to particularly productive individual active regions, and with approximately 11-year separations, owing to the solar-cycle ordering. However, these timescales would not explain any cosmogenic-isotope spikes requiring multiple extreme SEP events over consecutive years. [ABSTRACT FROM AUTHOR]

Near-duplicate video content has taken the large storage space in the age of big data. Without respecting the copyright ethic, social media users mirror, resize, and/or hide certain online video content and re-upload it as new data. This research aims to avoid the complex and high-dimensional matching and present an efficient approach for detecting near-duplicate videos, this detection is based on feature extraction using visual, motion, and high-level features. Fast and adaptive bidimensional empirical mode decomposition is used to preserve the relevant data to the furthest extent possible during the low/high-frequency transition and vice-versa. In addition, for a generic model, the invariant moments are added to the aforementioned features in order to reinforce them against different video transformations such as rotating and scaling. Furthermore, the video frames are divided into blocks with a fixed number of features, this set of features is represented by a signature, where its mean and standard deviation represents a single video map allowing easy similarity computation. The F1-score and accuracy are used to evaluate the results of this study; the relevant results are ranked by Top 1 for the best result, and the five top-ranked results are presented by Top 5 . Further, our result of Top 1 reached over 80% on F1-score, with a difference of ±4% from the Top 5 results, and it is over 90% on Accuracy using different datasets, such as UCF11, UCF50, and HDMB51. [ABSTRACT FROM AUTHOR]

This article presents news briefs scientific affairs. A lawsuit that accused arXiv, a preprint server for physics and astronomy papers, of religious discrimination has been thrown out of court on a technicality. The detection of tiny amounts of methane in the martian atmosphere has been continued by equipment on board the European Space Agency's orbiting Mars Express. The mystery surrounding the deaths of more than 300 Rocky Mountain elk in Wyoming has been attributed to overindulgence in a plant not found in their normal habitat.

Interest in asteroids is currently high in view of their scientific importance, the impact hazard, and the in situ resource opportunities they offer. They are also a case study of the intimate relationship between science and exploration. A detailed review of the twelve asteroids that have been visited by eight robotic spacecraft is presented here. While the twelve explored asteroids have many features in common, like their heavily cratered and regolith covered surfaces, they are a remarkably diverse group. Some have low-eccentricity orbits in the main belt, while some are potentially hazardous objects. They range from dwarf planets to primary planetesimals to fragments of larger precursor objects to tiny shards. One has a moon. Their surface compositions range from basaltic to various chondrite-like compositions. Here their properties are reviewed and what was confirmed and what was newly learned is discussed, and additionally the explored asteroids are compared with comets and meteorites. Several topics are developed. These topics are the internal structure of asteroids, water distribution in the inner solar system and its role in shaping surfaces, and the meteoritic links. It is suggested, that asteroid-scale grooves, ridges, and catenas on several explored asteroids argue against these asteroids having rubble pile interiors, i.e. interiors made when impact fragments reaccumulate. The only body for which this is not true is the tiny Itokawa and it is argued that this asteroid is a regolith breccia. The discovery of water on Vesta, fluidization textures on comets and possibly Eros, and the relatively large number of active asteroids inside the purported snowline, suggests that significant subsurface water may be present on asteroids in the inner solar system and may partly account for their low densities. The explored asteroids have also confirmed the linkage of the HED meteorites with Vesta and Itokawa with the ordinary chondrite meteorites, Eros is somewhat problematical. So while diversity, and the range of sizes, histories, and surface compositions, is the hall mark of the explored asteroids, the number of explored asteroids is small compared with the diversity of material expected on the basis of asteroid astronomy and meteorite geochemistry. The exploration of the solar system's asteroids has only just begun. [ABSTRACT FROM AUTHOR]

The article reviews an exhibition on the Soviet Union's achievements in outer space during the 20th century titled "Cosmonauts: Birth of the Space Age" at the Science Museum in London, England, on display until 16 March 2016.