1,324 research outputs found

    CFD and Wind Tunnel Study of the Performance of a Multi-Directional Wind Tower with Heat Transfer Devices

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    The aim of this work was to investigate the performance of a multi-directional wind tower integrated with heat transfer devices (HTD) using Computational Fluid Dynamics (CFD) and wind tunnel analysis. An experimental scale model was created using 3D printing. The scale model was tested in a closed-loop wind tunnel to validate the CFD data. Numerical results of the supply airflow were compared with experimental data. Good agreement was observed between both methods of analysis. Smoke visualisation test was conducted to analyse the air flow pattern in the test room attached underneath it. Results have indicated that the achieved indoor air speed was reduced by up to 17% following the integration of the cylindrical HTD. The effect of varying the number of HTD on the system's thermal performance were investigated. The work highlighted the potential of integrating HTD into wind towers in reducing the air temperature. The technology presented here is subject to a UK patent application (PCT/GB2014/052263)

    Energy efficiency and comfort in the workplace: Norwegian cellular and British open plan workplaces

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    Two office layouts with high and low levels of thermal control were compared, respectively Norwegian cellular and British open plan offices. The Norwegian practice provided every user with control over a window, blinds, door, and the ability to adjust heating and cooling. Occupants were expected to control their thermal environment to find their own comfort, while air conditioning was operating in the background to ensure the indoor air quality. In contrast, in the British office, limited thermal control was provided through openable windows and blinds only for occupants seated around the perimeter of the building. Centrally operated displacement ventilation was the main thermal control system. Users’ perception of thermal environment was recorded through survey questionnaires, empirical building performance through environmental measurements and thermal control through semi-structured interviews. The Norwegian office had 35% higher user satisfaction and 20% higher user comfort compared to the British open plan office. However, the energy consumption in the British practice was within the benchmark and much lower than the Norwegian office. Overall, a balance between thermal comfort and energy efficiency is required, as either extreme poses difficulties for the other

    Radiative Tau Lepton Pair Production as a Probe of Anomalous Electromagnetic Couplings of the Tau

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    We calculate the squared matrix element for the process e+ e- --> tau+ tau- gamma allowing for anomalous magnetic and electric dipole moments at the tau tau gamma vertex. No interferences are neglected and no approximations of light fermion masses are made. We show that anomalous moments affect not only the cross section, but also the shape of the photon energy and angular distributions. We also demonstrate that in the case of the anomalous magnetic dipole moment, the contribution from interference involving Standard Model and anomalous amplitudes is significant compared to the contribution from anomalous amplitudes alone. A program to perform the calculation is available and it may be employed as a Monte Carlo generator.Comment: 14 pages, 8 figures submitted to Nuclear Physics

    Genetic analysis of members of the species Oropouche virus and identification of a novel M segment sequence

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    Oropouche virus (OROV) is a public health threat in South America, and in particular Northern Brazil, causing frequent outbreaks of febrile illness. Using a combination of deep sequencing and Sanger sequencing approaches we have determined complete genome sequences of eight clinical isolates that were obtained from patient sera during an Oropouche fever outbreak in Amapa state, northern Brazil in 2009. We also report complete genome sequences of two OROV reassortants isolated from two marmosets in Minas Gerais state, southeast Brazil in 2012 that contain a novel M genome segment. Interestingly, all ten isolates posses a 947 nucleotide long S segment that lacks 11 residues in the S segment 3' UTR compared to the recently redetermined Brazilian prototype OROV strain BeAn19991. OROV maybe circulating more widely in Brazil and in the non-human primate population than previously appreciated and the identification of yet another reassortant highlights the importance of bunyavirus surveillance in South America

    Образ міста у творчості О. Іваненко (на матеріалі казки “Чарівна квітка”)

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    Авторка статті досліджує образ міста у творчості відомої письменниці ХХ ст. Оксани Іваненко. Автор робить спробу виокремити особливості творів, що характерні для її манери письма. Приділяється увага тематиці творів письменниці, портретній характеристиці її героїв. Дослідниця робить спробу схарактеризувати образ міста на матеріалі казок “Чарівна квітка”. “Місто боягузів” у казці “Чарівна квітка” О. Іваненко є точкою відліку в казковому часі, не має логіки у взаємозв’язку з дійсністю. Результатом дослідження є висновок про те, що письменниця досліджує процес становлення і розвитку дитини, вивчає особливості психології персонажів. Ключові слова: казка, логіка, образ, місто, тематика, реальність, персонажі.Автор статьи исследует образ города в творчестве известной писательницы ХХ века Оксаны Иваненко. Автор статьи делает попытку выделить особенности произведений, характерные ее письму. Уделяется внимание тематике произведений писательницы, портретной характеристике ее героев. Исследователь делает попытку охарактеризовать образ города на материале сказки “Волшебный цветок”. “Город боягузов” в сказке “Волшебный цветок” Оксаны Иваненко является точкой отсчета в сказочном времени, не имеет логики со взаимосвязью с действительностью. Результатом исследования является вывод о том, что писательница исследует процесс становления и развития юного читателя, изучает особенности психологии персонажей. Ключевые слова: сказка, логика, образ, город, тематика, реальность, персонажи.The author of the article investigates the figure of the city in the O. Ivanenko’s works, the famous writer of the XX th century. The author tries to define the peculiarities of her works. There are paid attentions to the portrait characteristics of the main characters in “Magic flower”, to the themes of her works. The investigator tries to characterise the figure of the city in the “Magic flower”. The “city of timorous people” in the “Magic flower” by O. Ivanenko is the beginning in the time of the tale, it does not have logic. This investigation proves that the writer investigates the process of the child’s growing and growing, studies the psychological peculiarities of the main characters. Keywords: tale, logic, figure, city, themes, reality, main characters

    Haloperidol and Ziprasidone for Treatment of Delirium in Critical Illness

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    BACKGROUND: There are conflicting data on the effects of antipsychotic medications on delirium in patients in the intensive care unit (ICU). METHODS: In a randomized, double-blind, placebo-controlled trial, we assigned patients with acute respiratory failure or shock and hypoactive or hyperactive delirium to receive intravenous boluses of haloperidol (maximum dose, 20 mg daily), ziprasidone (maximum dose, 40 mg daily), or placebo. The volume and dose of a trial drug or placebo was halved or doubled at 12-hour intervals on the basis of the presence or absence of delirium, as detected with the use of the Confusion Assessment Method for the ICU, and of side effects of the intervention. The primary end point was the number of days alive without delirium or coma during the 14-day intervention period. Secondary end points included 30-day and 90-day survival, time to freedom from mechanical ventilation, and time to ICU and hospital discharge. Safety end points included extrapyramidal symptoms and excessive sedation. RESULTS: Written informed consent was obtained from 1183 patients or their authorized representatives. Delirium developed in 566 patients (48%), of whom 89% had hypoactive delirium and 11% had hyperactive delirium. Of the 566 patients, 184 were randomly assigned to receive placebo, 192 to receive haloperidol, and 190 to receive ziprasidone. The median duration of exposure to a trial drug or placebo was 4 days (interquartile range, 3 to 7). The median number of days alive without delirium or coma was 8.5 (95% confidence interval [CI], 5.6 to 9.9) in the placebo group, 7.9 (95% CI, 4.4 to 9.6) in the haloperidol group, and 8.7 (95% CI, 5.9 to 10.0) in the ziprasidone group (P=0.26 for overall effect across trial groups). The use of haloperidol or ziprasidone, as compared with placebo, had no significant effect on the primary end point (odds ratios, 0.88 [95% CI, 0.64 to 1.21] and 1.04 [95% CI, 0.73 to 1.48], respectively). There were no significant between-group differences with respect to the secondary end points or the frequency of extrapyramidal symptoms. CONCLUSIONS: The use of haloperidol or ziprasidone, as compared with placebo, in patients with acute respiratory failure or shock and hypoactive or hyperactive delirium in the ICU did not significantly alter the duration of delirium. (Funded by the National Institutes of Health and the VA Geriatric Research Education and Clinical Center; MIND-USA ClinicalTrials.gov number, NCT01211522 .)

    A real-time olive fruit detection for harvesting robot based on YOLO algorithms

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    Deep neural network models have become powerful tools of machine learning and artificial intelligence. They can approximate functions and dynamics by learning from examples. This paper reviews the state-of-art of deep learning-based object detection frameworks that are used for fruit detection in general and for olive fruit in particular. A dataset of olive fruit on the tree is built to train and evaluate deep models. The ultimate goal of this work is the capability of on-edge real-time olive fruit detection on the tree from digital videos. Recent work in deep neural networks has led to the development of a state-of-the-art object detector termed You Only Look Once version five (YOLOv5). This paper builds a dataset of 1.2 K source images of olive fruit on the tree and evaluates the latest object detection algorithms focusing on variants of YOLOv5 and YOLOR. The results of the YOLOv5 models show that the YOLOv5 new network models are able to extract rich olive features from images and detect the olive fruit with a high precision of higher than 0.75 mAP_0.5. YOLOv5s performs better for real-time olive fruit detection on the tree over other YOLOv5 variants and YOLOR

    Fine Structure of Avalanches in the Abelian Sandpile Model

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    We study the two-dimensional Abelian Sandpile Model on a square lattice of linear size L. We introduce the notion of avalanche's fine structure and compare the behavior of avalanches and waves of toppling. We show that according to the degree of complexity in the fine structure of avalanches, which is a direct consequence of the intricate superposition of the boundaries of successive waves, avalanches fall into two different categories. We propose scaling ans\"{a}tz for these avalanche types and verify them numerically. We find that while the first type of avalanches has a simple scaling behavior, the second (complex) type is characterized by an avalanche-size dependent scaling exponent. This provides a framework within which one can understand the failure of a consistent scaling behavior in this model.Comment: 10 page

    Multiplicity Distributions in Canonical and Microcanonical Statistical Ensembles

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    The aim of this paper is to introduce a new technique for calculation of observables, in particular multiplicity distributions, in various statistical ensembles at finite volume. The method is based on Fourier analysis of the grand canonical partition function. Taylor expansion of the generating function is used to separate contributions to the partition function in their power in volume. We employ Laplace's asymptotic expansion to show that any equilibrium distribution of multiplicity, charge, energy, etc. tends to a multivariate normal distribution in the thermodynamic limit. Gram-Charlier expansion allows additionally for calculation of finite volume corrections. Analytical formulas are presented for inclusion of resonance decay and finite acceptance effects directly into the system partition function. This paper consolidates and extends previously published results of current investigation into properties of statistical ensembles.Comment: 53 pages, 7 figure
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