62 research outputs found

    FlexCore: Massively Parallel and Flexible Processing for Large MIMO Access Points

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    Large MIMO base stations remain among wireless network designers’ best tools for increasing wireless throughput while serving many clients, but current system designs, sacrifice throughput with simple linear MIMO detection algorithms. Higher-performance detection techniques are known, but remain off the table because these systems parallelize their computation at the level of a whole OFDM subcarrier, sufficing only for the less demanding linear detection approaches they opt for. This paper presents FlexCore, the first computational architecture capable of parallelizing the detection of large numbers of mutually-interfering information streams at a granularity below individual OFDM subcarriers, in a nearly-embarrassingly parallel manner while utilizing any number of available processing elements. For 12 clients sending 64-QAM symbols to a 12-antenna base station, our WARP testbed evaluation shows similar network throughput to the state-of-the-art while using an order of magnitude fewer processing elements. For the same scenario, our combined WARP-GPU testbed evaluation demonstrates a 19x computational speedup, with 97% increased energy efficiency when compared with the state of the art. Finally, for the same scenario, an FPGA-based comparison between FlexCore and the state of the art shows that FlexCore can achieve up to 96% better energy efficiency, and can offer up to 32x the processing throughput

    Problems of innovative receptivity of personnel of enterprises of industrial automation

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    Стаття присвячена аналізу галузі промислової автоматики (ПА), позначенню та з’ясовуванню проблематики у підприємств ПА для поліпшення інноваційної діяльності (ІД) шляхом комплексного підвищення інноваційної сприйнятливості (ІС) персоналу в системі управління персоналом. Показана динаміка виробничих економічних показників українських підприємств ПА за 2011-2017 рр., запропоновані рекомендації по підвищенню ІС персоналу. Наведено аналіз техніко-економічних показників підприємств ПА. Приведений загальний огляд реалізації продукції (товарів, послуг за видами економічної діяльності) на Україні за період 2010-2017 рр. Для дослідження приведена методологія порівняльного аналізу. Результати дослідження показують виявлення проблем підприємств ПA, які полягають у збільшенні реалізованої продукції і зниженні прибутку, що говорить про необхідність підвищення IС персоналу в системі управління персоналом.The article is devoted to the analysis of industrial areas in particular the field of industrial automation (ІA), the identification and clarification of problems in PA enterprises, to improve innovation activity (IА) through a comprehensive increase in the innovative receptivity (IR) of personnel in the personnel management system. The industrial enterprises of Ukraine and in particular industry of ІА now experiences heavy times of competitive activity with foreign companies and in particular with more cheap commodities from China. Not to lose the positions and occupy new markets it is needed not only to watch after novelties in the field of productive but also in the sphere of personnel and increase of him ІR for the increase of competitiveness. The dynamics of the production of economic indicators of the Ukrainian enterprises of IA for 2011-2017 is shown, recommendations for increasing the executive personnel are offered. The analysis of technical and economic indicators of IA enterprises is given. And also provides a general overview of the sale of products (goods, services by type of economic activity) in Ukraine for the period 2010-2017. For research methodology over of comparative analysis is brought. Research results are exposures of problems of enterprises of IA such as an increase of the realized products and decline of profit, that talks at the necessity of increase of IR of personnel, in control system by a personnel. Innovative activity of every enterprise of industrial automation (IA) is important for the increase of competitiveness and increase arrived. The innovative oriented skilled personnel failing in the Ukrainian enterprises, what called to provide development and increase of efficiency of activity of enterprises. For development normatively of technical documentation on a management and development of personnel experience of front-rank world companies is poorly used what track is adapted to take into account taking into account Ukrainian realities. To the necessity of development of control system by a personnel with the purpose of leading to of them to the standards of front-rank world companies

    Female Chimpanzees Use Copulation Calls Flexibly to Prevent Social Competition

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    The adaptive function of copulation calls in female primates has been debated for years. One influential idea is that copulation calls are a sexually selected trait, which enables females to advertise their receptive state to males. Male-male competition ensues and females benefit by getting better mating partners and higher quality offspring. We analysed the copulation calling behaviour of wild female chimpanzees (Pan troglodytes schweinfurthii) at Budongo Forest, Uganda, but found no support for the male-male competition hypothesis. Hormone analysis showed that the calling behaviour of copulating females was unrelated to their fertile period and likelihood of conception. Instead, females called significantly more while with high-ranking males, but suppressed their calls if high-ranking females were nearby. Copulation calling may therefore be one potential strategy employed by female chimpanzees to advertise receptivity to high-ranked males, confuse paternity and secure future support from these socially important individuals. Competition between females can be dangerously high in wild chimpanzees, and our results indicate that females use their copulation calls strategically to minimise the risks associated with such competition

    Male Mating Tactics in Captive Rhesus Macaques (Macaca mulatta): The Influence of Dominance, Markets, and Relationship Quality

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    Male mating success in a multimale–multifemale group can depend on several variables: body condition, dominance, coalitions, “friendship,” or an exchange of services for mating access. Exchange patterns may also be determined by market effects or social relationships. We studied the mating tactics of males in a captive, multimale–multifemale group of rhesus macaques and the resulting patterns of mating and paternity to determine the influence of dominance rank, mating markets, and relationship quality on their mating tactics. Male rank was positively related to the total number of copulations and the number of mating partners, but did not explain male mating distribution completely. Moreover, male fertilization success was not related to male rank. Males did not exchange grooming for mating access on the same day and neither the supply nor the rank (as a proxy for quality) of receptive females affected the amount of male grooming, suggesting that market effects did not explain male mating access. However, there was a positive correlation between long-term grooming patterns of both males and females and mating access, indicating that social relationships were important for male mating access. Paternity data revealed that these social relationships were also important for male reproductive success. We conclude that both male rank and male–female “friendship” determined male mating access in these rhesus macaques, but that “friendship” was more important in determining paternity, emphasizing the importance of intersex social bonds in male mating success in multimale primate societies

    Mating skew in Barbary macaque males: the role of female mating synchrony, female behavior, and male–male coalitions

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    A fundamental question of sexual selection theory concerns the causes and consequences of reproductive skew among males. The priority of access (PoA) model (Altmann, Ann NY Acad Sci 102:338–435, 1962) has been the most influential framework in primates living in permanent, mixed-sex groups, but to date it has only been tested with the appropriate data on female synchrony in a handful of species. In this paper, we used mating data from one large semi-free ranging group of Barbary macaques: (1) to provide the first test of the priority-of-access model in this species, using mating data from 11 sexually active females (including six females that were implanted with a hormonal contraceptive but who showed levels of sexual activity comparable to those of naturally cycling females) and (2) to determine the proximate mechanism(s) underlying male mating skew. Our results show that the fit of the observed distribution of matings with sexually attractive females to predictions of the PoA model was poor, with lower-ranking males mating more than expected. While our work confirms that female mating synchrony sets an upper limit to monopolization by high-ranking individuals, other factors are also important. Coalitionary activity was the main tactic used by males to lower mating skew in the study group. Coalitions were expressed in a strongly age-related fashion and allowed subordinate, post-prime males to increase their mating success by targeting more dominant, prime males. Conversely, females, while mating promiscuously with several males during a given mating cycle, were more likely to initiate their consortships with prime males, thus reducing the overall effectiveness of coalitions. We conclude that high-ranking Barbary macaque males have a limited ability to monopolize mating access, leading to a modest mating skew among them

    Sex-specific reproductive behaviours and paternity in free-ranging Barbary macaques (Macaca sylvanus)

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    In a wide variety of species, male reproductive success is determined by contest for access to females. Among multi-male primate groups, however, factors in addition to male competitive ability may also influence paternity outcome, although their exact nature and force is still largely unclear. Here, we have investigated in a group of free-ranging Barbary macaques whether paternity is determined on the pre- or postcopulatory level and how male competitive ability and female direct mate choice during the female fertile phase are related to male reproductive success. Behavioural observations were combined with faecal hormone analysis for timing of the fertile phase (13 cycles, 8 females) and genetic paternity analysis (n = 12). During the fertile phase, complete monopolisation of females did not occur. Females were consorted for only 49% of observation time, and all females had ejaculatory copulations with several males. Thus, in all cases, paternity was determined on the postcopulatory level. More than 80% of infants were sired by high-ranking males, and this reproductive skew was related to both, male competitive ability and female direct mate choice as high-ranking males spent more time in consort with females than low-ranking males, and females solicited copulations mainly from dominant males. As most ejaculatory copulations were female-initiated, female direct mate choice appeared to have the highest impact on male reproductive success. However, female preference was not directly translated into paternity, as fathers were not preferred over non-fathers in terms of solicitation, consortship and mating behaviour. Collectively, our data show that in the Barbary macaque, both sexes significantly influence male mating success, but that sperm of several males generally compete within the female reproductive tract and that therefore paternity is determined by mechanisms operating at the postcopulatory level

    Underlying Mechanisms of Gene–Environment Interactions in Externalizing Behavior: A Systematic Review and Search for Theoretical Mechanisms

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    Maximum likelihood detection of spatially multiplexed signals via loosely ordered depth-first sphere decoding

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    The complexity of depth-first sphere decoders (SDs) is determined by the employed tree search and pruning strategies. Proposed is a new SD approach for maximum-likelihood (ML) detection of spatially multiplexed, high-order, QAM symbols. In contrast to typical ML approaches, the proposed tree traversal skips the computationally intensive requirement of visiting the nodes in ascending order of their partial distances (PDs). Then, a new pruning method efficiently narrows the search space and preserves the ML performance despite the non-ordered tree traversal. This proposed approach results in substantially reduced PD calculations when compared to typical ML SDs and, for high SNRs, the necessary calculations can be reduced down to the number of transmit antennas. © 2012 The Institution of Engineering and Technology
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