bluuebunny/crossref_metadata_2025 huggingface dataset:
The Use of Drones in Spain: Towards a Platform for Controlling UAVs in Urban Environments
Authors: Chamoso Pablo , González-Briones Alfonso , Rivas Alberto , Bueno De Mata Federico , Corchado Juan Manuel
Published: May 2018

Rapid advances in technology make it necessary to prepare our society in every aspect. Some of the most significant technological developments of the last decade are the UAVs (Unnamed Aerial Vehicles) or drones. UAVs provide a wide range of new possibilities and have become a tool that we now use on a daily basis. However, if their use is not controlled, it could entail several risks, which make it necessary to legislate and monitor UAV flights to ensure, inter alia, the security and privacy of all citizens. As a result of this problem, several laws have been passed which seek to regulate their use; however, no proposals have been made with regards to the control of airspace from a technological point of view. This is exactly what we propose in this article: a platform with different modes designed to control UAVs and monitor their status. The features of the proposed platform provide multiple advantages that make the use of UAVs more secure, such as prohibiting UAVs’ access to restricted areas or avoiding collisions between vehicles. The platform has been successfully tested in Salamanca, Spain.
A Method for Estimating the Polarimetric Scattering Matrix of Moving Target for Simultaneous Fully Polarimetric Radar
Authors: Wang Fulai , Li Chao , Pang Chen , Li Yongzhen , Wang Xuesong
Published: May 2018

To precisely obtain the polarimetric scattering matrix (PSM) of moving target, a measurement model for the simultaneous fully polarimetric radar is formulated. The calibration errors and isolation of the transmitted waveforms are considered. To address the decline in performance of the traditional PSM estimation methods when the target moves, a novel method with measurement selection is proposed. Numerical experiments are conducted to demonstrate and validate the superiority of the proposed method, especially for the PSM estimation of the target with non-uniform motion.
Distributed Fast Self-Organized Maps for Massive Spectrophotometric Data Analysis †
Authors: Dafonte Carlos , Garabato Daniel , Álvarez Marco A. , Manteiga Minia
Published: May 2018

Analyzing huge amounts of data becomes essential in the era of Big Data, where databases are populated with hundreds of Gigabytes that must be processed to extract knowledge. Hence, classical algorithms must be adapted towards distributed computing methodologies that leverage the underlying computational power of these platforms. Here, a parallel, scalable, and optimized design for self-organized maps (SOM) is proposed in order to analyze massive data gathered by the spectrophotometric sensor of the European Space Agency (ESA) Gaia spacecraft, although it could be extrapolated to other domains. The performance comparison between the sequential implementation and the distributed ones based on Apache Hadoop and Apache Spark is an important part of the work, as well as the detailed analysis of the proposed optimizations. Finally, a domain-specific visualization tool to explore astronomical SOMs is presented.
A Finite State Machine Approach to Algorithmic Lateral Inhibition for Real-Time Motion Detection †
Authors: López María T. , Bermúdez Aurelio , Montero Francisco , Sánchez José L. , Fernández-Caballero Antonio
Published: May 2018

Many researchers have explored the relationship between recurrent neural networks and finite state machines. Finite state machines constitute the best-characterized computational model, whereas artificial neural networks have become a very successful tool for modeling and problem solving. The neurally-inspired lateral inhibition method, and its application to motion detection tasks, have been successfully implemented in recent years. In this paper, control knowledge of the algorithmic lateral inhibition (ALI) method is described and applied by means of finite state machines, in which the state space is constituted from the set of distinguishable cases of accumulated charge in a local memory. The article describes an ALI implementation for a motion detection task. For the implementation, we have chosen to use one of the members of the 16-nm Kintex UltraScale+ family of Xilinx FPGAs. FPGAs provide the necessary accuracy, resolution, and precision to run neural algorithms alongside current sensor technologies. The results offered in this paper demonstrate that this implementation provides accurate object tracking performance on several datasets, obtaining a high F-score value (0.86) for the most complex sequence used. Moreover, it outperforms implementations of a complete ALI algorithm and a simplified version of the ALI algorithm—named “accumulative computation”—which was run about ten years ago, now reaching real-time processing times that were simply not achievable at that time for ALI.
A Cross-Layer Optimized Opportunistic Routing Scheme for Loss-and-Delay Sensitive WSNs
Authors: Xu Xin , Yuan Minjiao , Liu Xiao , Liu Anfeng , Xiong Neal N. , Cai Zhiping , Wang Tian
Published: May 2018

In wireless sensor networks (WSNs), communication links are typically error-prone and unreliable, so providing reliable and timely data routing for loss- and delay-sensitive applications in WSNs it is a challenge issue. Additionally, with specific thresholds in practical applications, the loss and delay sensitivity implies requirements for high reliability and low delay. Opportunistic Routing (OR) has been well studied in WSNs to improve reliability for error-prone and unreliable wireless communication links where the transmission power is assumed to be identical in the whole network. In this paper, a Cross-layer Optimized Opportunistic Routing (COOR) scheme is proposed to improve the communication link reliability and reduce delay for loss-and-delay sensitive WSNs. The main contribution of the COOR scheme is making full use of the remaining energy in networks to increase the transmission power of most nodes, which will provide a higher communication reliability or further transmission distance. Two optimization strategies referred to as COOR(R) and COOR(P) of the COOR scheme are proposed to improve network performance. In the case of increasing the transmission power, the COOR(R) strategy chooses a node that has a higher communication reliability with same distance in comparison to the traditional opportunistic routing when selecting the next hop candidate node. Since the reliability of data transmission is improved, the delay of the data reaching the sink is reduced by shortening the time of communication between candidate nodes. On the other hand, the COOR(P) strategy prefers a node that has the same communication reliability with longer distance. As a result, network performance can be improved for the following reasons: (a) the delay is reduced as fewer hops are needed while the packet reaches the sink in longer transmission distance circumstances; (b) the reliability can be improved since it is the product of the reliability of every hop of the routing path, and the count is reduced while the reliability of each hop is the same as the traditional method. After analyzing the energy consumption of the network in detail, the value of optimized transmission power in different areas is given. On the basis of a large number of experimental and theoretical analyses, the results show that the COOR scheme will increase communication reliability by 36.62–87.77%, decrease delay by 21.09–52.48%, and balance the energy consumption of 86.97% of the nodes in the WSNs.
Sci—An Open Access Journal with Post-Publication Peer Review
Authors: Rittman Martyn , Vazquez Franck
Published: May 2018

Sci (ISSN: 2413-4155) is a new and innovative open access journal from MDPI. [...]
Running in Someone Else’s Shoes: The Electoral Consequences of Running as an Appointed Senator
Authors: Eaves Carrie
Published: May 2018

Over the past century, nearly two hundred times a governor has appointed an individual to fill a vacant Senate seat. This research seeks to understand the electoral fates of these appointed senators. First, I address the question of when and under what conditions an appointed senator will choose to run for reelection to the seat. Then, should they choose to run for that office in the next election, they are in the rare position of being an incumbent who has not previously won an election to that particular office. Although these appointed senators are not on equal footing as other first-term senators, they still provide a unique circumstance worthy of further examination. I find that those appointed senators who had previously held an elected office were more likely to run to maintain the Senate seat. I also find that appointed senators fare slightly worse than other first-term senators did when campaigning for reelection.
Using Certification as a Tool to Develop Sustainability in Project Management
Authors: Martínez-Perales Silvia , Ortiz-Marcos Isabel , Juan Ruiz Jesús , Lázaro Francisco Javier
Published: May 2018

Sustainability is a field of growing interest in Project Management (PM). Literature on Sustainability in PM is abundant at a theoretical level; however, it is necessary to explore hands-on approaches for designing models and practices. The purpose of this study is to introduce management systems as a practical tool for Sustainability in PM. Management system certifications are used as an indicator of the implementation of Sustainability practices, and thus, the impact of Sustainability on the success of projects is analyzed. The methodology for this study includes the analysis of the correspondence between Sustainability and five recognized management system standards (ISO 9001, ISO 14001, ISO 50001, UNE 166002 and OHSAS 18001) and experimental research based on data delivered by CDTI (Center for Industrial Technological Development) including relevant and objective information about R&D&I Projects in the energy sector. This study analyzes the impact of four variables (duration, budget, year of funding and certifications to management systems) on the success of the project. The conclusion is the significant positive impact of having management system certifications on the success of company projects analyzed in the Spanish energy sector, which may be of interest to PM practitioners in order to consider Sustainability as a factor for success.
Mechanism for Controlling Floor Heave of Mining Roadways Using Reinforcing Roof and Sidewalls in Underground Coal Mine
Authors: Guo Gangye , Kang Hongpu , Qian Deyu , Gao Fuqiang , Wang Yang
Published: May 2018

Controlling floor heave plays an important role in the stability of mining roadways that is pivotal to the sustainable, safe, and efficient development of coal resources in underground coal mines. In order to propose highly efficient and economical methods of controlling floor heave, numerical simulation, laboratory physical simulation, and engineering practice were carried out to reveal the mechanism of reinforcing roof and sidewalls to control the floor heave of the mining roadway, return airway 15208, in the Xinjing Coal Mine in the Yanquan mining area of China. The numerical simulation demonstrated that the surrounding rock of the roadway underwent expansion and deformation, accompanied by redistribution of the surrounding rock stress due to the reinforcement of the roof and two sidewalls. The laboratory physical simulation revealed that the reinforcing roof and sidewalls decreased the bed separation of the floor and reduced the quantity of the displacement of the floor in Coal Seam 15. Engineering practice showed that the floor heave in the roadway, the roof, and the sidewalls, which was reinforced by intensive bolts combined with steel belt, wire mesh, and cable, was significantly reduced compared with that with lower supporting intensity of roof and sidewalls. The floor heave could be successfully controlled.
Farmers’ and Consumers’ Preferences for Drinking Water Quality Improvement through Land Management Practices: The Case Study of the Soyang Watershed in South Korea
Authors: Lee Saem , Kim Hyun , Nguyen Trung , Koellner Thomas , Shin Hio-Jung
Published: May 2018

The drinking water quality along the Soyang watershed has been affected negatively by the intensive agricultural practices in the upstream area. Our study used a choice experiment method in order to estimate the values that the upstream water providers (i.e., farmers) and downstream water users (i.e., consumers) attach to the following attributes, namely, the agricultural profits, water quality, and biodiversity level of the Soyang watershed in South Korea. The preferences of the upstream water providers and downstream water users were presented by a conditional logit model and with interactions. The results from the conditional logit model specifications revealed that water quality is the most important attribute that is preferred by the downstream water users and upstream farmers. Both the upstream farmers and downstream water users have put substantial values on the protection of water bodies in the Soyang watershed, and are concerned about the consequences of water usage on the environment and human health. The respondents in each income group and in different local communities with income levels seemed to have different implicit costs for the water quality improvement in the Soyang watershed. Our study has provided robust results regarding the benefits of water improvement using sustainable land management and can be considered as a fundamental input for aiding the sustainable water–land nexus policies. We suggest that the government carefully designs a policy so as to compensate the highland farmers for their income losses as a result of the changing farming practices.
Computational Analysis of the Interaction Energies between Amino Acid Residues of the Measles Virus Hemagglutinin and Its Receptors
Authors: Xu Fengqi , Tanaka Shigenori , Watanabe Hirofumi , Shimane Yasuhiro , Iwasawa Misako , Ohishi Kazue , Maruyama Tadashi
Published: May 2018

Measles virus (MV) causes an acute and highly devastating contagious disease in humans. Employing the crystal structures of three human receptors, signaling lymphocyte-activation molecule (SLAM), CD46, and Nectin-4, in complex with the measles virus hemagglutinin (MVH), we elucidated computationally the details of binding energies between the amino acid residues of MVH and those of the receptors with an ab initio fragment molecular orbital (FMO) method. The calculated inter-fragment interaction energies (IFIEs) revealed a number of significantly interacting amino acid residues of MVH that played essential roles in binding to the receptors. As predicted from previously reported experiments, some important amino-acid residues of MVH were shown to be common but others were specific to interactions with the three receptors. Particularly, some of the (non-polar) hydrophobic residues of MVH were found to be attractively interacting with multiple receptors, thus indicating the importance of the hydrophobic pocket for intermolecular interactions (especially in the case of Nectin-4). In contrast, the electrostatic interactions tended to be used for specific molecular recognition. Furthermore, we carried out FMO calculations for in silico experiments of amino acid mutations, finding reasonable agreements with virological experiments concerning the substitution effect of residues. Thus, the present study demonstrates that the electron-correlated FMO method is a powerful tool to search exhaustively for amino acid residues that contribute to interactions with receptor molecules. It is also applicable for designing inhibitors of MVH and engineered MVs for cancer therapy.
Shintō as Written Representation: The Phases and Shifts of Medieval Shintō Texts
Authors: Abe Yasurō
Published: May 2018

Le présent article essaie de situer dans l'histoire les doctrines du shintō médiéval et leurs sources (jingisho) selon une méthode philologique. Il est notoire que beaucoup de textes qui appartiennent à la catégorie des textes du shintō de tendance Shingon (Shingon Shintō) sont des apocryphes, et que leurs auteurs et leurs dates de composition sont difficiles à déterminer. La même chose peut être dite pour bien des ouvrages du Shintō.

Dans la bibliothèque monastique du Shinpukuji Hoshōin (appelée aussi l'Ōsu bunko), qui abrite de nombreux manuscrits du Moyen Âge, principalement des textes de l'ésotérisme, on trouve beaucoup de textes du Shingon Shintō et du Shintō d'Ise, qui contiennent des informations précieuses.

Parmi ces manuscrits, il existe un ouvrage intitulé Yaketsu, en douze fascicules, et un nombre important de textes (en tout cent quatre-vingts fascicules) qui sont en rapport étroit avec lui et forment un ensemble de manuscrits cohérent (ce qu'on appelle gusho). Ces manuscrits ont été copiés par Yūe, disciple à la fois de Nōshin, le premier abbé du Shinpukuji, et de Gikai, qui lui avait transmis ces textes appartenant à la lignée de Sanbōin-ryū ; ils constituent une transmission de la lignée Sanbōin-goryū. À l'aide du Catalogue de cet ensemble de textes, le Yaketsu mokuroku, nous pouvons restituer le contenu systématique de cette lignée de rituels. D'autre part, les colophons inclus dans certains de ces manuscrits permettent de comprendre que ces textes sont des documents de transmission secrets que le Prince en dharma (liosshinnō), Shūkaku du Ninnaji a reçus de Shōkaku du Sanbōin, et qu'il a lui-même compilés sous cette forme. Si cette origine peut être confirmée, on peut penser que les textes du Shingon Shintō relatifs au sanctuaire d'Ise ont été compilés au cours de la période dite des empereurs retirés (Inseiki), pendant le processus de la formation et du développement des différentes lignées de l'ésotérisme Shingon.

Au cœur de ce groupe d'ouvrages du Shingon Shintō, on trouve des textes comme le Nisho Tenshō kōtaijin, le Ryōkū keimon jinshaku, le Tenshō daijin senkō jidaishō, ou le Jishō tosō(qui est identique au Jinshō tōtsūki). On peut relever dans un de ces textes une citation du fameux ouvrage du Shinto d'Ise, le Yamatohime no mikoto seiki.

Ainsi, il est possible que ces textes de l'ensemble de manuscrits Yaketsu gusho contiennent des indices importants permettant de situer historiquement la formation des ouvrages et du discours du shintō médiéval.
On the Formation of Shintō Icons
Authors: Atsushi Kadoya
Published: May 2018

Dans les ouvrages du shintō médiéval, il existe un certain nombre d'icônes mystérieuses qui n'ont été guère étudiées jusqu'à présent. Nous essaierons d'avancer ici quelques hypothèses sur la formation de ces icônes. On peut se poser trois questions principales à leur propos : 1° celle de leurs origines ; 2° celle de leurs rapports à la formation des théories shintoïstes ; 3° celle de leur rôle dans les rituels pratiques.

Dans le présent essai, nous nous proposons d'examiner la première de ces questions, à savoir les origines possibles de ces icônes. Celles-ci peuvent être classées en cinq grandes catégories :

a) images des kami

b) mishōtai ou « Augustes Vrais Corps », c'est-à-dire les kami symbolisés sous forme de miroirs

c) joyaux à souhait (Hōshu sk. cintâmani,)

d) objets naturels (roches, arbres, courants d'eau, etc.)

e) symboles ou emblèmes

II n'y a aucun doute que les icônes shintoïstes ont été créées sous l'influence massive de l'iconographie du bouddhisme ésotérique. Cependant, cette seule influence ne saurait tout expliquer. D'autres sources doivent être supposées. Ici, nous avançons l'hypothèse d'une possible influence du taoïsme. En effet, nous pouvons reconnaître des traits qui semblent relever d'une telle influence dans certaines représentations des costumes des divinités, des objets naturels ou des symboles graphiques.

Nous prendrons un exemple intéressant qui est l'image de la déesse Amaterasu dans le Reikiki : elle a l'apparence du bodhisattva Memyō, une divinité qui relève du bouddhisme ésotérique. Cependant, ce bodhisattva lui-même a une origine chinoise. De plus, cette image ressemble, sous certains aspects, à celle de la divinité taoïste appelée Tianguan (« Fonctionnaire Céleste »). Nous analyserons cette ressemblance, et proposerons l'hypothèse d'une possible influence de l'imagerie taoïste sur la formation de l'imagerie du shintō médiéval.
Matara: A Dream King Between Insight and Imagination
Authors: Bodiford William M.
Published: May 2018

Le présent article examine une divinité appelée Matara qui était à l'origine puissante, mais dont le culte a été réprimé avant de tomber dans l'oubli. Les précédentes études sur cette divinité ayant été influencées par cette répression, elles ont mis l'accent sur son caractère soi-disant hétérogène, « combinatoire », peu orthodoxe ou déviant. Après une brève revue des théories les plus remarquables de ces précédentes études, nous introduisons les ouvrages d'un prélat Tendai de l'époque Edo, Jōin (1682-1739), qui avait reçu une initiation complète sur les secrets de Matara. Jōin présente Matara comme le roi des rêves, jouant un rôle essentiel dans les pratiques orthodoxes de méditation du bouddhisme de l'Asie orientale. L'exposé de Jōin nous aide à situer ce rôle dans son contexte. Il ne s'agit pas de « pratiques orthodoxes de méditation » dans les spectacles populaires et dans le folklore. Jōin explique également pourquoi Matara en vint à apparaître comme le dieu de la souveraineté pour la famille Tokugawa et pour Tenkai, le maître bouddhiste qui avait établi, selon les rites du Sannō ichijitsu shintō, le culte de Tokugawa Ieyasu (1542-1616) à Nikkō Bit en tant que Tōshō Daigongen. Suivant cette explication, Jōin identifie le droit divin de gouvernement comme relevant du « shintō » et affirme que seul ce dernier (et non le bouddhisme) est capable d'assurer la paix et la prospérité du royaume.
Prendre appui sur la diversité linguistique et culturelle pour développer aussi la langue commune
Authors: Perregaux Christiane
Published: May 2018

La mondialisation et, notamment, la mobilité des populations a modifié la place et le statut du français, qui doit accepter de vivre, jusque dans l’école, avec d’autres langues également légitimes. La reconnaissance de ce changement, qui s’opère parfois avec de grandes résistances, modifie la relation aux langues des enseignants et celle des élèves, qui sont assez fréquemment plurilingues. La description et l’analyse sociolinguistique des situations individuelles et collectives, sociétales, familiales et scolaires révèlent alors des situations linguistiques très complexes. L’émergence d’une compréhension nouvelle de ces situations, où le plurilinguisme perd son exceptionnalité et le monolinguisme sa normalité, aurait donc une influence sur l’enseignement / apprentissage qui ne négligerait plus ce que certains appellent le déjà là ou les arrières plans de l’apprentissage. Les ressources des élèves demandent alors à être reconnues et à être introduites dans des propositions didactiques. Certaines sont avancées dans le présent article. C’est dans cet environnement plurilinguistique que s’inscrit aujourd’hui l’enseignement / apprentissage du français.
Les Portfolios européens des langues : des outils plurilingues pour une culture éducative partagée
Authors: Castellotti Véronique
Published: May 2018

El desarrollo del plurilingüismo constituye un punto desde ahora importante en las políticas educativas europeas, tal y como se encuentran definidas en el marco europeo de referencia común para las lenguas en 2001 y tal y como se las encuentra en los Portafolios europeos de las lenguas. La competencia plurilingüe aparece como un objetivo privilegiado del aprendizaje, a través, sobre todo, de la toma de conciencia y de la evaluación de los alumnos de su biografía lingüística, testigo de repertorios plurales y diversificados. Nuestro estudio tiene por objetivo mostrar como los portafolios de la escuela primaria y el colegio se inscriben directamente dentro de las orientaciones europeas de apertura al plurilingüismo y a la pluralidad, favoreciento la consideración de contactos entre diversas lenguas, apoyando la realización de las representaciones positivas de las lenguas y de su aprentizaje, y permitiendo a los alumnos la valorización y la construcción de las competencias plurilingües, que incluyen al mismo tiempo las lenguas primeras y las otras lenguas aprendidas.
Le dépassement du conflit diglossique en Corse : implications pédagogiques et didactiques chez les maîtres bilingues de l’école primaire
Authors: Cortier Claude
Published: May 2018

It is an established fact that Corsican teachers do not elude the effects of diglossia on any individual. Nevertheless, the implementation in state primary schools of Corsican and French bilingual teaching relying on an equal hourly representation, entitles to anticipate the richness of experiences in such fields as mutual relations and the management of school multilingualism. Using a set of audio and video recordings done in february 2004 in five bilingual school sites in

Corsica, this research endeavours to match in a relevant way the sociolinguistic and didactic aspects of the implementation of bi(multi) lingualism. What emerges from all that is that the introduction of Corsican at school results in the surpassment of diglossia, restores the social role of primary school in the management of cultural diversities, acts on motivation, prepares to individual bilingualism and backs up the didactics of languages and of language (both written and oral).
L’écriture de fiction : un objet introuvable dans l’école de la République ?
Authors: Jey Martine
Published: May 2018

À partir de 1880, les activités d’écriture, dans l’ordre primaire, se voient accorder une plus grande importance ; l’écriture de fiction, néanmoins, y reste marginale. Conçu pour donner, en un temps bref, un nombre limité de connaissances, l’ordre primaire privilégie les activités d’écriture impliquant l’observation et centrées sur le vécu de l’élève. Dans les sujets de rédaction analysés, le rapport du fictif et du vécu est complexe, ambivalent. Artificiel, le vécu est parfois fictionnalisé. Assimilée à la feinte, au mensonge, la fiction se trouve de fait marginalisée dans une institution dont les objectifs principaux sont de moraliser, de faire intégrer des codes de comportement familiaux, sociaux, patriotiques. Elle permet aussi de discipliner l’imagination, de garder la maîtrise de ce qui apparaît comme un danger.
Fiction-imagination-écrit-école : quelques remarques
Authors: François Frédéric
Published: May 2018

Frédéric François, Universidad Paris 5.

Nos hemos permitido permanecer a una cierta distancia de la prácticas pedagógicas para proponer algunas observaciones sobre tres puntos : la difi cultad que encontramos al utilizar la dicotomía «fi cción-realidad » ; la propuesta de recurrir al juego de la tensión entre los diversos snetidos de «imaginario» antes que a esta dicotomía. Algunos aspectos de la especifi cidad de las relaciones entre lo imaginario, el escrito y el colegio.
Les écritures de soi à l’école primaire : bref historique d’un genre scolaire
Authors: Bishop Marie-France
Published: May 2018

Marie-France Bishop, IUFM du Nord-Pas-de-Calais, THÉODILE.

Las producciones escritas sobre sí mismo en la escuela son raramente consideradas como un género escolar particular. Sin embargo, poseen rasgos recurrentes y se inscriben dentro de una historia ligada a las transformaciones de los conceptos de la escritura escolar. Este artículo propone bosquejar los principales trazos de un recorrido histórico a través del cual la vivencia de los alumnos va a ser más o menos solicitada, en función de los los objetivos de la enseñanza. Dos grandes objetivos se alternan : escribir para aprender a escribir o escribir para expresarse. En función de la elección realizada y de las prioridades dadas a la redacción, las producciones escritas sobre sí mismo ocuparán un lugar más o menos importante.
Superresolution Interferometric Imaging with Sparse Modeling Using Total Squared Variation: Application to Imaging the Black Hole Shadow
Authors: Kuramochi Kazuki , Akiyama Kazunori , Ikeda Shiro , Tazaki Fumie , Fish Vincent L. , Pu Hung-Yi , Asada Keiichi , Honma Mareki
Published: May 2018

We propose a new imaging technique for interferometry using sparse modeling, utilizing two regularization terms: the ℓ
1-norm and a new function named total squared variation (TSV) of the brightness distribution. First, we demonstrate that our technique may achieve a superresolution of ∼30% compared with the traditional CLEAN beam size using synthetic observations of two point sources. Second, we present simulated observations of three physically motivated static models of Sgr A* with the Event Horizon Telescope (EHT) to show the performance of proposed techniques in greater detail. Remarkably, in both the image and gradient domains, the optimal beam size minimizing root-mean-squared errors is ≲10% of the traditional CLEAN beam size for ℓ
1+TSV regularization, and non-convolved reconstructed images have smaller errors than beam-convolved reconstructed images. This indicates that TSV is well matched to the expected physical properties of the astronomical images and the traditional post-processing technique of Gaussian convolution in interferometric imaging may not be required. We also propose a feature-extraction method to detect circular features from the image of a black hole shadow and use it to evaluate the performance of the image reconstruction. With this method and reconstructed images, the EHT can constrain the radius of the black hole shadow with an accuracy of ∼10%–20% in present simulations for Sgr A*, suggesting that the EHT would be able to provide useful independent measurements of the mass of the supermassive black holes in Sgr A* and also another primary target, M87.
Synthesis of Molecular Oxygen via Irradiation of Ice Grains in the Protosolar Nebula
Authors: Mousis O. , Ronnet T. , Lunine J. I. , Maggiolo R. , Wurz P. , Danger G. , Bouquet A.
Published: May 2018

Molecular oxygen has been detected in the coma of comet 67P/Churyumov–Gerasimenko with a mean abundance of 3.80 ± 0.85% by the ROSINA mass spectrometer on board the Rosetta spacecraft. To account for the presence of this species in comet 67P/Churyumov–Gerasimenko, it has been shown that the radiolysis of ice grain precursors of comets is a viable mechanism in low-density environments, such as molecular clouds. Here, we investigate the alternative possibility that the icy grains present in the midplane of the protosolar nebula were irradiated during their vertical transport between the midplane and the upper layers over a large number of cycles, as a result of turbulent mixing. Consequently, these grains spent a non-negligible fraction of their lifetime in the disk’s upper regions, where the irradiation by cosmic rays was strong. To do so, we used a coupled disk-transport-irradiation model to calculate the time evolution of the molecular oxygen abundance radiolytically produced in ice grains. Our computations show that, even if a significant fraction of the icy particles has followed a back and forth cycle toward the upper layers of the disk over tens of millions of years, a timespan far exceeding the formation timescale of comet 67P/Churyumov–Gerasimenko, the amount of produced molecular oxygen is at least two orders of magnitude lower than the Rosetta observations. We conclude that the most likely scenario remains the formation of molecular oxygen in low-density environments, such as the presolar cloud, prior to the genesis of the protosolar nebula.
Using Star Clusters as Tracers of Star Formation and Chemical Evolution: The Chemical Enrichment History of the Large Magellanic Cloud*
Authors: Chilingarian Igor V. , Asa’d Randa
Published: May 2018

The star formation (SFH) and chemical enrichment (CEH) histories of Local Group galaxies are traditionally studied by analyzing their resolved stellar populations in a form of color–magnitude diagrams obtained with the Hubble Space Telescope. Star clusters can be studied in integrated light using ground-based telescopes to much larger distances. They represent snapshots of the chemical evolution of their host galaxy at different ages. Here we present a simple theoretical framework for the chemical evolution based on the instantaneous recycling approximation (IRA) model. We infer a CEH from an SFH and vice versa using observational data. We also present a more advanced model for the evolution of individual chemical elements that takes into account the contribution of supernovae type Ia. We demonstrate that ages, iron, and α-element abundances of 15 star clusters derived from the fitting of their integrated optical spectra reliably trace the CEH of the Large Magellanic Cloud obtained from resolved stellar populations in the age range 40 Myr < t < 3.5 Gyr. The CEH predicted by our model from the global SFH of the LMC agrees remarkably well with the observed cluster age–metallicity relation. Moreover, the present-day total gas mass of the LMC estimated by the IRA model (

) matches within uncertainties the observed H i mass corrected for the presence of molecular gas (

). We briefly discuss how our approach can be used to study SFHs of galaxies as distant as 10 Mpc at the level of detail that is currently available only in a handful of nearby Milky Way satellites.
SARAS 2 Constraints on Global 21 cm Signals from the Epoch of Reionization*
Authors: Singh Saurabh , Subrahmanyan Ravi , Shankar N. Udaya , Rao Mayuri Sathyanarayana , Fialkov Anastasia , Cohen Aviad , Barkana Rennan , Girish B. S. , Raghunathan A. , Somashekar R. , Srivani K. S.
Published: May 2018

Spectral distortions in the cosmic microwave background over the 40–200 MHz band are imprinted by neutral hydrogen in the intergalactic medium prior to the end of reionization. This signal, produced in the redshift range z = 6–34 at the rest-frame wavelength of 21 cm, has not been detected yet; and a poor understanding of high-redshift astrophysics results in a large uncertainty in the expected spectrum. The SARAS 2 radiometer was purposely designed to detect the sky-averaged 21 cm signal. The instrument, deployed at the Timbaktu Collective (Southern India) in 2017 April–June, collected 63 hr of science data, which were examined for the presence of the cosmological 21 cm signal. In our previous work, the first-light data from the SARAS 2 radiometer were analyzed with Bayesian likelihood-ratio tests using 264 plausible astrophysical scenarios. In this paper we reexamine the data using an improved analysis based on the frequentist approach and forward-modeling. We show that SARAS 2 data reject 20 models, out of which 15 are rejected at a significance >5σ. All the rejected models share the scenario of inefficient heating of the primordial gas by the first population of X-ray sources, along with rapid reionization.
Shock Acceleration of Electrons and Synchrotron Emission from the Dynamical Ejecta of Neutron Star Mergers
Authors: Lee Shiu-Hang , Maeda Keiichi , Kawanaka Norita
Published: May 2018

Neutron star mergers (NSMs) eject energetic subrelativistic dynamical ejecta into circumbinary media. Analogous to supernovae and supernova remnants, the NSM dynamical ejecta are expected to produce nonthermal emission by electrons accelerated at a shock wave. In this paper, we present the expected radio and X-ray signals by this mechanism, taking into account nonlinear diffusive shock acceleration (DSA) and magnetic field amplification. We suggest that the NSM is unique as a DSA site, where the seed relativistic electrons are abundantly provided by the decays of r-process elements. The signal is predicted to peak at a few 100–1000 days after the merger, determined by the balance between the decrease of the number of seed electrons and the increase of the dissipated kinetic energy, due to the shock expansion. While the resulting flux can ideally reach the maximum flux expected from near-equipartition, the available kinetic energy dissipation rate of the NSM ejecta limits the detectability of such a signal. It is likely that the radio and X-ray emission are overwhelmed by other mechanisms (e.g., an off-axis jet) for an observer placed in a jet direction (i.e., for GW170817). However, for an off-axis observer, to be discovered once a number of NSMs are identified, the dynamical ejecta component is predicted to dominate the nonthermal emission. While the detection of this signal is challenging even with near-future facilities, this potentially provides a robust probe of the creation of r-process elements in NSMs.
TRGB Distances to Galaxies in Front of the Virgo Cluster
Authors: Karachentsev Igor D. , Makarova Lidia N. , Tully R. Brent , Rizzi Luca , Shaya Edward J.
Published: May 2018

Tip of the red giant branch distances are acquired from Hubble Space Telescope images for 16 galaxies to the foreground of the Virgo Cluster. The new distances with 5% accuracy, combined with archival measurements, tightly constrain the near-side location of the onset of infall into the Virgo Cluster to be 7.3 ± 0.3 Mpc from the cluster, reaching within 9 Mpc of the Milky Way. The mass within this turnaround radius about the cluster is (8.3 ± 0.9) × 1014
M
⊙. Color–magnitude diagrams are provided for galaxies in this study and there is a brief discussion of their group affiliations.
Detection of Intrinsic Spin Alignments in Isolated Spiral Pairs
Authors: Koo Hanwool , Lee Jounghun
Published: May 2018

Observational evidence for intrinsic galaxy alignments in isolated spiral pairs is presented. From the catalog of the galaxy groups identified by Tempel et al. in the flux-limited galaxy sample of the Sloan Digital Sky Survey Data Release 10, we select those groups consisting only of two spiral galaxies as isolated spiral pairs and investigate if and how strongly the spin axes of their two spiral members are aligned with each other. We detect a clear signal of intrinsic spin alignment in isolated spiral pairs, which leads to the rejection of the null hypothesis at the 99.9999% confidence level via the Rayleigh test. It is also found that those isolated pairs comprising two early-type spiral galaxies exhibit the strongest signal of intrinsic spin alignment and that the strength of the alignment signal depends on the angular separation distance as well as on the luminosity ratio of the member galaxies. Using the dark matter halos consisting of only two subhalos resolved in the EAGLE hydrodynamic simulations, we repeat the same analysis but fail to find any alignment tendency between the spin angular momentum vectors of the stellar components of the subhalos, which is in tension with the observational result. Several possible sources of this apparent inconsistency between the observational and the numerical results are discussed.
The Volumetric Rate of Calcium-rich Transients in the Local Universe
Authors: Frohmaier Chris , Sullivan Mark , Maguire Kate , Nugent Peter
Published: May 2018

We present a measurement of the volumetric rate of “calcium-rich” optical transients in the local universe, using a sample of three events from the Palomar Transient Factory (PTF). This measurement builds on a detailed study of the PTF transient detection efficiencies and uses a Monte Carlo simulation of the PTF survey. We measure the volumetric rate of calcium-rich transients to be higher than previous estimates:

events yr−1 Mpc−3. This is equivalent to 33%–94% of the local volumetric Type Ia supernova rate. This calcium-rich transient rate is sufficient to reproduce the observed calcium abundances in galaxy clusters, assuming an asymptotic calcium yield per calcium-rich event of ∼0.05

. We also study the PTF detection efficiency of these transients as a function of position within their candidate host galaxies. We confirm as a real physical effect previous results that suggest that calcium-rich transients prefer large physical offsets from their host galaxies.
Spatially Resolved Stellar Kinematics from LEGA-C: Increased Rotational Support in z ∼ 0.8 Quiescent Galaxies
Authors: Bezanson Rachel , van der Wel Arjen , Pacifici Camilla , Noeske Kai , Barišić Ivana , Bell Eric F. , Brammer Gabriel B. , Calhau Joao , Chauke Priscilla , van Dokkum Pieter , Franx Marijn , Gallazzi Anna , van Houdt Josha , Labbé Ivo , Maseda Michael V. , Muños-Mateos Juan Carlos , Muzzin Adam , van de Sande Jesse , Sobral David , Straatman Caroline , Wu Po-Feng
Published: May 2018

We present stellar rotation curves and velocity dispersion profiles for 104 quiescent galaxies at z = 0.6–1 from the Large Early Galaxy Astrophysics Census (LEGA-C) spectroscopic survey. Rotation is typically probed across 10–20 kpc, or to an average of 2.7R

e
. Combined with central stellar velocity dispersions (σ
0) this provides the first determination of the dynamical state of a sample selected by a lack of star formation activity at large lookback time. The most massive galaxies (M
⋆ > 2 × 1011
M
⊙) generally show no or little rotation measured at 5 kpc (

∣

V

5

∣

/

σ

0

<
0.2

in eight of ten cases), while ∼64% of less massive galaxies show significant rotation. This is reminiscent of local fast- and slow-rotating ellipticals and implies that low- and high-redshift quiescent galaxies have qualitatively similar dynamical structures. We compare

∣

V

5

∣

/

σ

0

distributions at z ∼ 0.8 and the present day by re-binning and smoothing the kinematic maps of 91 low-redshift quiescent galaxies from the Calar Alto Legacy Integral Field Area (CALIFA) survey and find evidence for a decrease in rotational support since z ∼ 1. This result is especially strong when galaxies are compared at fixed velocity dispersion; if velocity dispersion does not evolve for individual galaxies then the rotational velocity at 5 kpc was an average of 94 ± 22% higher in z ∼ 0.8 quiescent galaxies than today. Considering that the number of quiescent galaxies grows with time and that new additions to the population descend from rotationally supported star-forming galaxies, our results imply that quiescent galaxies must lose angular momentum between z ∼ 1 and the present, presumably through dissipationless merging, and/or that the mechanism that transforms star-forming galaxies also reduces their rotational support.
Host Star Dependence of Small Planet Mass–Radius Distributions
Authors: Neil Andrew R. , Rogers Leslie A.
Published: May 2018

The planet formation environment around M dwarf stars is different than around G dwarf stars. The longer hot protostellar phase, activity levels and lower protoplanetary disk mass of M dwarfs all may leave imprints on the composition distribution of planets. We use hierarchical Bayesian modeling conditioned on the sample of transiting planets with radial velocity mass measurements to explore small planet mass–radius distributions that depend on host star mass. We find that the current mass–radius data set is consistent with no host star mass dependence. These models are then applied to the Kepler planet radius distribution to calculate the mass distribution of close-orbiting planets and how it varies with host star mass. We find that the average heavy element mass per star at short orbits is higher for M dwarfs compared to FGK dwarfs, in agreement with previous studies. This work will facilitate comparisons between microlensing planet surveys and Kepler, and will provide an analysis framework that can readily be updated as more M dwarf planets are discovered by ongoing and future surveys such as K2 and the Transiting Exoplanet Survey Satellite.
A importância da infraestrutura de transporte para o desenvolvimento do estado de Goiás
Authors: Martins Vera Lúcia Francisco Dias , Parreira Kerima Martins , Vieira Jeferson Castro
Published: May 2018

Este artigo analisa a efetividade dos programas de investimento em infraestrutura de transporte do Estado de Goiás que, devido a sua localização geográfica, tende a impactar diretamente no desenvolvimento do país. Destaca os planejamentos para investimentos na infraestrutura rodoviária, aérea e ferroviária nesta região durante o período de 2006 a 2014. Apresenta dado obtido junto ao Portal da Transparência do Estado de Goiás, Secretaria de Estado de Gestão e Planejamento de Goiás, Portal Brasil, Programa de Investimento em Logística e Instituto Mauro Borges. Por fim, demonstra falhas na capacidade da execução orçamentária, comprometendo, o aumento do investimento em infraestrutura logística com reflexos no desenvolvimento nacional.
Territorialidade, políticas públicas e o agronegócio com foco no desenvolvimento
Authors: Catapan Anderson , Oliveira Antonio Gonçalves de
Published: May 2018

Este editorial apresenta os artigos do terceiro número do sexto volume da Revista Brasileira de Planejamento e Desenvolvimento (RBPD). Este número trouxe contribuições para o planejamento e desenvolvimento, assim como em números anteriores e já de praxe deste periódico, de professores do Brasil e de diversos outros países.
Influência do tempo de mistura lenta no uso de quiabo como floculante aplicado associado ao policloreto de alumínio
Authors: Lima Bruna Caroline , Pinguelo Gigliolla Caroline Biason , Vernasqui Laís Gimenes , Teixeira Guilherme Gobbi , Silva-Medeiros Flávia Vieira
Published: May 2018

O objetivo deste estudo foi verificar a influência do tempo de mistura lenta (TML) na aplicação do polímero natural quiabo como floculante no tratamento de águas para abastecimento. Para isso, foram realizados ensaios variando o TML de 10 a 40 minutos.  As concentrações do coagulante químico, do quiabo e do alcalinizante foram fixadas em 10, 0,3 e 5 ppm, respectivamente. Os melhores resultados de cor e turbidez foram obtidos para os TML de 15 e 40 min, que devido à semelhança dos resultados, indicam que o aumento do TML não apresentou melhora significativa na água tratada. Ainda é possível perceber também que a associação do quiabo com o PAC apresentou resultados melhores se comparados aos encontrados na utilização do quiabo combinado com o sulfato de alumínio, conforme encontrado na literatura, indicando a eficiência desse floculante também com o PAC.
Qualidade microbiológica de leites UHT comercializados na cidade de Ouro Preto, MG.
Authors: Cioglia Camila Rodrigues , De Freitas Maria Tereza
Published: May 2018

O leite é um alimento de alto valor nutricional e, ao mesmo tempo, é um excelente meio para o crescimento de microrganismos, que podem ser patogênicos e prejudiciais para o homem, ou deteriorar o produto. Embora o tratamento em Ultra Alta Temperatura (UHT ou UAT) seja aplicado para garantir a segurança microbiológica e aumentar a vida útil do produto, a literatura referente à avaliação microbiológica de leites UHT traz relatos de falhas do processo. O objetivo deste trabalho foi averiguar a qualidade microbiológica de leites UHT comercializados no município de Ouro Preto – MG, por meio da contagem de bactérias mesófilas, psicrotróficas, termófilas e de esporos mesófilos aeróbios. Foi utilizado o método convencional para detecção de cada um desses microrganismos de acordo com as orientações da Instrução Normativa nº 62 do Ministério da Agricultura e Pecuária. O resultado das análises demonstrou que as amostras de leites UHT, em sua maioria, não apresentaram microrganismos indicadores de deficiências no processo ou de qualidade da matéria-prima.