Forming efficient agent groups for completing complex tasks

In this paper we produce complexity and impossibility results and develop algorithms for a task allocation problem that needs to be solved by a group of autonomous agents working together. In particular, each task is assumed to be composed of several subtasks and involves an associated predetermined and known overall payment (set by the task’s owner) for its completion. However, the division of this payment among the corresponding contributors is not predefined. Now to accomplish a particular task, all its subtasks need to be allocated to agents with the necessary capabilities and the agents’ corresponding costs need to fall within the preset overall task payment. For this scenario, we first provide a cooperative agent system designer with a practical solution that achieves an efficient allocation. However, this solution is not applicable for non-cooperative settings. Consequently, we go on to provide a detailed analysis where we prove that certain design goals cannot be achieved if the agents are self interested. Specifically, we prove that for the general case, no protocol achieving the efficient solution can exist that is individually rational and budget balanced. We show that although efficient protocols may exist in some settings, these will inevitably be setting-specific

УНІВЕРСИТЕТСЬКІ ІННОВАЦІЙНІ ХАБИ ЯК ТОЧКИ РОСТУ ІНДУСТРІАЛЬНИХ ПАРКІВ УКРАЇНИ

The purpose of the article is generalization of features of expediency of the creation of innovative parks in Ukraine. Practical output of the results consists in the discovered success factors of the activity of innovative parks in Ukraine in order to create new opportunities of innovation development of the country. Current organizational and functional system of innovative entrepreneurship of Ukraine is an imperfect, complex and by all indications, is in the process of formation. It is assumed that infrastructure of international educational innovative hub can structurally corrected according to the area which operates a hub that is: stimulate the dialogue between academics, businessmen and government officials; provide an interactive exchange of explicit and implicit knowledge; generate shared vision on adaptation measures of dynamic environment. Evaluation of the results of scientific and pedagogical activities of working group of innovative hub should be made for following indicators: development of skills of teaching and research work; introducing of innovative approaches for practical individual activity; formation of innovative approaches for collective practical activity; working on the chosen scientific and methodological theme. Main advantage of proposed university innovative hubs is that laid all necessary foundations in order to high school could be as soon as effectively integrate the results of university, academic and sectoral sciences of Ukraine, well as advanced research results of scientific world community in the development and implementation of innovative projects and development innovationДосліджено індустріальні парки України та дано їх загальну характеристику. Запропоновано авторське бачення змісту програми реалізації інноваційного проєкту «університетський інноваційний хаб». Розкрито можливості інноваційної самоідентифікації університетів України шляхом формування освітніх хабів в інноваційному глобальному просторі та їхні взаємовідносини в межах Рамкової програми ЄС з наукових досліджень й інновацій. У ході дослідження було виявлено, що сучасна організаційно-функціональна система інноваційного підприємництва України є недосконалою, складною і за всіма ознаками перебуває на стадії модернізації. Передбачається, що інфраструктура міжнародного освітнього інноваційного хабу може структурно корегуватися відповідно до галузі, в якій функціонує індустріальний парк, що, у свою чергу, закладатиме базис до колективного створення різного роду інновацій з урахуванням потенціалу технологій, техніки, знань й компетенцій; дозволить інтерактивний обмін явними і неявними знаннями; дасть змогу сформувати спільне бачення щодо заходів адаптації динамічного (гіперзмінного) середовища. Наведено характерні особливості очікуваних впливів у результаті роботи університетських інноваційних хабів. Оцінку результатів науково-педагогічної діяльності робочої групи інноваційного хабу запропоновано проводити за такими показниками: розвиток навичок науково-дослідної роботи; впровадження інноваційних підходів до практичної індивідуальної та колективної діяльності; робота над обраною науково-методичною темою. Практична цінність одержаних результатів полягає у виявленні факторів успіху діяльності інноваційних парків на базі університетських хабів з метою створення нових можливостей інноваційного розвитку економіки України. Основна перевага запропонованих університетських інноваційних хабів полягає в тому, що закладені всі необхідні основи для того, щоб вища школа змогла б якнайшвидше інтегрувати результати університетських, академічних та галузевих наук України, а також передові результати досліджень наукової світової спільноти, у реалізацію інноваційних проєктів та розвиток інновацій

The High-Order-Multiplicity of Unusually Wide M-dwarf Binaries: Eleven New Triple and Quadruple Systems

M-dwarfs in extremely wide binary systems are very rare, and may thus have different formation processes from those found as single stars or close binaries in the field. In this paper we search for close companions to a new sample of 36 extremely wide M-dwarf binaries, covering a spectral type range of M1 to M5 and a separation range of 600 - 6500 AU. We discover 10 new triple systems and one new quadruple system. We carefully account for selection effects including proper motion, magnitude limits, the detection of close binaries in the SDSS, and other sample biases. The bias-corrected total high-order-multiple fraction is 45% (+18%/-16%) and the bias-corrected incidence of quadruple systems is < 5%, both statistically compatible with that found for the more common close M-dwarf multiple systems. Almost all the detected companions have similar masses to their primaries, although two very low mass companions, including a candidate brown dwarf, are found at relatively large separations. We find that the close-binary separation distribution is strongly peaked towards < 30AU separations. There is marginally significant evidence for a change in high-order M-dwarf multiplicity with binding energy and total mass. We also find 2-sigma evidence of an unexpected increased high-order-multiple fraction for the widest targets in our survey, with a high-order-multiple fraction of 21% (+17%/-7%) for systems with separations up to 2000AU, compared to 77% (+9%/-22%) for systems with separations > 4000AU. These results suggest that the very widest M-dwarf binary systems need higher masses to form or to survive.Comment: 11 pages, 14 figures, accepted for publication in Ap

Two Wide Planetary-mass Companions to Solar-type Stars in Upper Scorpius

At wide separations, planetary-mass and brown dwarf companions to solar-type stars occupy a curious region of parameter space not obviously linked to binary star formation or solar system scale planet formation. These companions provide insight into the extreme case of companion formation (either binary or planetary), and due to their relative ease of observation when compared to close companions, they offer a useful template for our expectations of more typical planets. We present the results from an adaptive optics imaging survey for wide (~50–500 AU) companions to solar-type stars in Upper Scorpius. We report one new discovery of a ~14 M_J companion around GSC 06214−00210and confirm that the candidate planetary-mass companion 1RXS J160929.1−210524 detected by Lafrenière et al. is in fact comoving with its primary star. In our survey, these two detections correspond to ~4% of solar-type stars having companions in the 6–20 M_J mass and ~200–500 AU separation range. This figure is higher than would be expected if brown dwarfs and planetary-mass companions were drawn from an extrapolation of the binary mass function. Finally, we discuss implications for the formation of these objects

A Stellar Census of the Tucana-Horologium Moving Group

We report the selection and spectroscopic confirmation of 129 new late-type (K3-M6) members of the Tuc-Hor moving group, a nearby (~40 pc), young (~40 Myr) population of comoving stars. We also report observations for 13/17 known Tuc-Hor members in this spectral type range, and that 62 additional candidates are likely to be unassociated field stars; the confirmation frequency for new candidates is therefore 129/191 = 67%. We have used RVs, Halpha emission, and Li6708 absorption to distinguish contaminants and bona fide members. Our expanded census of Tuc-Hor increases the known population by a factor of ~3 in total and by a factor of ~8 for members with SpT>K3, but even so, the K-M dwarf population of Tuc-Hor is still markedly incomplete. The spatial distribution of members appears to trace a 2D sheet, with a broad distribution in X and Y, but a very narrow distribution (+/-5 pc) in Z. The corresponding velocity distribution is very small, with a scatter of +/-1.1 km/s about the mean UVW velocity. We also show that the isochronal age (20--30 Myr) and the lithium depletion age (40 Myr) disagree, following a trend seen in other PMS populations. The Halpha emission follows a trend of increasing EW with later SpT, as seen for young clusters. We find that members have been depleted of lithium for spectral types of K7.0-M4.5. Finally, our purely kinematic and color-magnitude selection procedure allows us to test the efficiency and completeness for activity-based selection of young stars. We find that 60% of K-M dwarfs in Tuc-Hor do not have ROSAT counterparts and would be omitted in Xray selected samples. GALEX UV-selected samples using a previously suggested criterion for youth achieve completeness of 77% and purity of 78%. We suggest new selection criteria that yield >95% completeness for ~40 Myr populations.(Abridged)Comment: Accepted to AJ; 28 pages, 12 figures, 5 tables in emulateapj forma

Two Wide Planetary-Mass Companions to Solar-Type Stars in Upper Scorpius

At wide separations, planetary-mass and brown dwarf companions to solar type stars occupy a curious region of parameters space not obviously linked to binary star formation or solar-system scale planet formation. These companions provide insight into the extreme case of companion formation (either binary or planetary), and due to their relative ease of observation when compared to close companions, they offer a useful template for our expectations of more typical planets. We present the results from an adaptive optics imaging survey for wide (50-500 AU) companions to solar type stars in Upper Scorpius. We report one new discovery of a ~14 M_J companion around GSC 06214-00210, and confirm that the candidate planetary mass companion 1RXS J160929.1-210524 detected by Lafreniere et al (2008) is in fact co-moving with its primary star. In our survey, these two detections correspond to ~4% of solar type stars having companions in the 6-20 M_J mass and 200-500 AU separation range. This figure is higher than would be expected if brown dwarfs and planetary mass companions were drawn from an extrapolation of the binary mass function. Finally, we discuss implications for the formation of these objects.Comment: 11 Pages, 7 Figures, Accepted for Ap

The ability to move to a beat is linked to the consistency of neural responses to sound

The ability to synchronize movement to a steady beat is a fundamental skill underlying musical performance and has been studied for decades as a model of sensorimotor synchronization. Nevertheless, little is known about the neural correlates of individual differences in the ability to synchronize to a beat. In particular, links between auditory-motor synchronization ability and characteristics of the brain's response to sound have not yet been explored. Given direct connections between the inferior colliculus (IC) and subcortical motor structures, we hypothesized that consistency of the neural response to sound within the IC is linked to the ability to tap consistently to a beat. Here, we show that adolescent humans who demonstrate less variability when tapping to a beat have auditory brainstem responses that are less variable as well. One of the sources of this enhanced consistency in subjects who can steadily tap to a beat may be decreased variability in the timing of the response, as these subjects also show greater between-trial phase-locking in the auditory brainstem response. Thus, musical training with a heavy emphasis on synchronization of movement to musical beats may improve auditory neural synchrony, potentially benefiting children with auditory-based language impairments characterized by excessively variable neural responses

Neural responses to sounds presented on and off the beat of ecologically valid music

The tracking of rhythmic structure is a vital component of speech and music perception. It is known that sequences of identical sounds can give rise to the percept of alternating strong and weak sounds, and that this percept is linked to enhanced cortical and oscillatory responses. The neural correlates of the perception of rhythm elicited by ecologically valid, complex stimuli, however, remain unexplored. Here we report the effects of a stimulus' alignment with the beat on the brain's processing of sound. Human subjects listened to short popular music pieces while simultaneously hearing a target sound. Cortical and brainstem electrophysiological onset responses to the sound were enhanced when it was presented on the beat of the music, as opposed to shifted away from it. Moreover, the size of the effect of alignment with the beat on the cortical response correlated strongly with the ability to tap to a beat, suggesting that the ability to synchronize to the beat of simple isochronous stimuli and the ability to track the beat of complex, ecologically valid stimuli may rely on overlapping neural resources. These results suggest that the perception of musical rhythm may have robust effects on processing throughout the auditory system

Conserved current for the Cotton tensor, black hole entropy and equivariant Pontryagin forms

The Chern-Simons lagrangian density in the space of metrics of a 3-dimensional manifold M is not invariant under the action of diffeomorphisms on M. However, its Euler-Lagrange operator can be identified with the Cotton tensor, which is invariant under diffeomorphims. As the lagrangian is not invariant, Noether Theorem cannot be applied to obtain conserved currents. We show that it is possible to obtain an equivariant conserved current for the Cotton tensor by using the first equivariant Pontryagin form on the bundle of metrics. Finally we define a hamiltonian current which gives the contribution of the Chern-Simons term to the black hole entropy, energy and angular momentum.Comment: 13 page