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Made-to-measure galaxy modelling utilising absorption line strength data

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research in Astronomy and Astrophysics 2016年第12期16卷 89-100页

作者： r.j.Long National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China jodrell Bank Centre for Astrophysics School of Physics and Astronomythe University of ManchesterOxford RoadManchester M13 9PLUK

We enhance the Syer ＆ Tremaine made-to-measure （M2M） particle method of stellar dynamical modelling to model simultaneously both kinematic data and absorption line strength data, thus creating a ＇chemo-M2M＇ modelling scheme. We apply the enhanced method to four galaxies （NGC 1248, NGC 3838, NGC 4452, NGC 4551） observed using the SAUrON integral-field spectrograph as part of the ATLAS3D programme. We are able to reproduce successfully the 2D line strength data achieving mean X2 per bin values of ≈ 1 with 〉 95% of particles having converged weights. Because M2M uses a 3D particle system, we are also able to examine the underlying 3D line strength distributions. The extent to which these dis- tributions are plausible representations of real galaxies requires further consideration. Overall, we consider the modelling exercise to be a promising first step in developing a ＇chemo-M2M＇ modelling system and in understanding some of the issues to be addressed. While the made-to-measure techniques developed have been applied to absorption line strength data, they are in fact general and may be of value in modelling other aspects of galaxies.

关键词： galaxies: abundances --galaxies: formation- galaxies: individual (NGC 1248 NGC 3838,NGC 4452 NGC 4551) -- galaxies: kinematics and dynamics -- galaxies: structure -- methods: numerical

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致病性奈瑟氏菌的动物模型

国外医学（微生物学分册） 1989年第6期12卷 263-265,266页

作者： Arko r.j 李自力

本文叙述了淋球菌和脑膜炎球菌的动物模型。淋球菌可用黑猩猩建立局限性尿道感染,非灵长类实验动物模型以近交系小鼠应用较广。豚鼠、家兔、大鼠及仓鼠均有一定的实用价值。脑膜炎球菌感染动物模型可使用猴、兔、豚鼠、小鼠及鸡胚,但以... 详细信息

本文叙述了淋球菌和脑膜炎球菌的动物模型。淋球菌可用黑猩猩建立局限性尿道感染,非灵长类实验动物模型以近交系小鼠应用较广。豚鼠、家兔、大鼠及仓鼠均有一定的实用价值。脑膜炎球菌感染动物模型可使用猴、兔、豚鼠、小鼠及鸡胚,但以各种近交系小鼠是为通用,小鼠腹腔内感染已用于检测脑膜炎球菌菌株变异和阐明代谢铁在脑膜炎感染中的作用,还能区别脑膜炎球菌不同毒力菌株。

关键词：奈瑟氏动物模型

Managing advertising campaigns-an approximate planning approach

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Frontiers of Computer Science 2012年第2期6卷 209-229页

作者： SertanGIrGIN jérémieMArY PhilippePrEUX OlivierNICOL Team—pr.jectSequeL INRIALilleNordEuropeVilleneuved’Ascq59650France LIFLUMrCNrS Universit6deLilleVilleneuved’Ascq59650France

We consider the problem of displaying commer- cial advertisements on web pages, in the ＂cost per click＂ model. The advertisement server has to learn the appeal of each type of visitor for the different advertisements in order to maximize the profit. Advertisements have constraints such as a certain number of clicks to draw, as well as a lifetime. This problem is thus inherently dynamic, and intimately com- bines combinatorial and statistical issues. To set the stage, it is also noteworthy that we deal with very rare events of in- terest, since the base probability of one click is in the or- der of 10-4. Different approaches may be thought of, rang- ing from computationally demanding ones （use of Markov decision processes, or stochastic programming） to very fast ones. We introduce NOSEED, an adaptive policy learning al- gorithm based on a combination of linear programming and multi-arm bandits. We also propose a way to evaluate the extent to which we have to handle the constraints （which is directly related to the computation cost）. We investigate the performance of our system through simulations on a realistic model designed with an important commercial web actor.

关键词： advertisement selection web sites optimiza-tion non-stationary setting linear programming multi-armbandit click-through rate (CTr) estimation exploration-exploitation trade-off

Mechanism of soft x-ray continuum radiation from low-energy pinch discharges of hydrogen and ultra-low field ignition of solid fuels

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Plasma Science and Technology 2017年第9期19卷 7-34页

作者： r MILLS j LOTOSKI Y LU Brilliant Light Power Inc.493 Old Trenton RoadCranburyNJ 08512United States of America

EUV continuum radiation（10–30 nm） arising only from very low energy pulsed pinch gas discharges comprising some hydrogen was first observed at Black Light Power, Inc. and reproduced at the Harvard Center for Astrophysics（Cf A）. The source was determined to be due to the transition of H to the lower-energy hydrogen or hydrino state H（1/4） whose emission matches that observed wherein alternative sources were eliminated. The identity of the catalyst that accepts 3 · 27.2 eV from the H to cause the H to H（1/4） transition was determined to HOH versus 3H. The mechanism was elucidated using different oxide-coated electrodes that were selective in forming HOH versus plasma forming metal atoms as well as from the intensity profile that was a mismatch for the multi-body reaction required during 3H catalysis. The HOH catalyst was further shown to give EUV radiation of the same nature by igniting a solid fuel comprising a source of H and HOH catalyst by passing a low voltage, high current through the fuel to produce explosive plasma. No chemical reaction can release such high-energy light. No high field existed to form highly ionized ions that could give radiation in this EUV region that persisted even without power input. This plasma source serves as strong evidence for the existence of the transition of H to hydrino H（1/4） by HOH as the catalyst and a corresponding new power source wherein initial extraordinarily brilliant light-emitting prototypes are already producing photovoltaic generated electrical power. The hydrino product of a catalyst reaction of atomic hydrogen was analyzed by multiple spectroscopic techniques. Moreover, the m H catalyst was identified to be active in astronomical sources such as the Sun, stars and interstellar medium wherein the characteristics of hydrino match those of the dark matter of the Universe.

关键词： ignition continuum brilliant catalysis matches elucidated reproduced spectroscopic figure helium

Assessing the vulnerability of Dutch water bodies to exotic species： A new methodology

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Current Zoology 2011年第6期57卷 863-873页

作者： r.j. LEEWIS A. GITTENBErGEr Netherlands Centre for Biodiversity Naturalis P.O. Box 9517 2300 RA Leiden The Netherlands GiMarIS Bioscience Park Leiden J.H. Oortweg 21 23.33 CH Leden The N etherlands. Institute of Environmental Sciences （CML） Leiden University P.O. Box 9518 2300 Leiden The Netherlands

Invasive exotic （alien） species have not been taken into enough consideration concerning the European Water Framework Directive （WFD） and other European directives until recently. The Dutch ministry responsible for water management is looking for ways to establish the impacts that invasive alien species may have on specified water types. This paper concentrates on the vulnerability of such water types to the introduction of exotic species. This new approach focusses on the system where the alien species are introduced into rather than only on the alien species themselves. We propose an equation that combines threats to and in water types with effects of particular species （observed or prognosticated）. Numerical values used in the formula have been found by scoring a number of properties in different water types and species, which are specified in questionnaires. The results of the calculations are given as relative vulnerability scores （scale 1-10）. By testing as many as 8 water types and 13 species, we demonstrate that this method is flexible and easy to use for water managers. Our results can be translated into classes of vulner- ability, which are represented on geographical maps with colour codes to indicate different degrees of vulnerability in the different water bodies. This readily corresponds to the way countries are required to report to the European Union in the context of the WFD. The method can also be generalized using functional groups of （exotic） species instead of particular species

关键词： Exotic species risk analysis Vulnerability Methodology European Water Framework Directive Water types

Polymer Sensitized Quasi Solid-State Photovoltaic Cells Using Derivatives of Polythiophene

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journal of Materials Science & Technology 2006年第6期22卷 811-816页

作者： G.K.r.Senadeera j.M.r.C.Fernando Institute of Fundamental Studies Hantane RoadKandySri Lanka Institute of Fundamental Studies Hantane RoadKandySri Lanka Postgraduate Institute of ScienceUniversity of PeradeniyaPeradeniyaSri Lanka

Substituted thiophene sensitized, nanocrystalline TiO2-based quasi solid-state solar cells were fabricated by using either poly （3-thiophene acetic acid）（P3TAA） or a copolymer with poly （3-thiophene acetic acid）-poly （hexyl thiophene）（P3TAA-PHT） polymers and copper iodide （Cul） as a hole conducting material together with an ionic liquid 1-ethyl-3-methylimidazolium bis （trifluoromethylsulfonyl） amide and lithium bis （triflu- oromethanesulfone） imide as additives for charge transport promotion. Dramatic enhancements in the cell performances were observed with the additives in Cul. While the cell sensitized with P3TAA generated a short-circuit photocurrent of -1.45 ***^-2, an open-circuit photovoltage of -345 mV with a total power conversion efficiency of -0.3% under simulated full sunlight of 100 mW-cm^-2 （air mass： 1.5）, the cell sensitized with copolymer P3TAA-PHT delivered -0.25% efficiency under the same conditions with -1.23 mA-cm^-2 as photocurrent and -371 mV as photovoltage.

关键词： Solar cells Polymers Titanium dioxide

Euler Deconvolution with Improved Accuracy and Multiple Different Structural Indices

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journal of China University of Geosciences 2008年第1期19卷 72-76页

作者： G r.j Cooper School of Geosciences University of the Witwatersrand Johannesburg 2050 South Africa

Euler deconvolution is a semi-automatic interpretation method that is frequently used with magnetic and gravity data. For a given source type, which is specified by its structural index （SI）, it provides an estimate of the source location. It is demonstrated here that by computing the solution space of individual data points and selecting common source locations the accuracy of the result can be improved. Furthermore, only a slight modification of the method is necessary to allow solutions for any number of different Sls to be obtained simultaneously. The method is applicable to both evenly and unevenly sampled geophysical data and is demonstrated on gravity and magnetic data. Source code （in Matlab format） is available from ***.

关键词： semi-automatic interpretation magnetics gravity geophysics.

An improve d smoothe d particle hydrodynamics approach using new inverse kernel function

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journal of Ocean Engineering and Science 2022年第4期7卷 327-336页

作者： j.r.r.japriyadharshini Department of Civil Engineering Thiagarajar College of EngineeringMaduraiTNIndia

The main limitation of Smoothed Particle Hydrodynamics(SPH)method that resists the method’s poten-tial is its lack of providing stability and accuracy to the numerical *** improve the accuracy of the standard SPH technique,by formulating a new inverse logarithmic kernel *** new kernel function is derived based on the underlying properties of kernel *** approximation technique used here is based on the Moving Least Squares based *** adequacy of the proposed ker-nel function is tested by simulation of 2D shock wave propagation and 3D dam-break free surface flow against a cuboidal *** method was validated against experimental data by Kleefsman et al.,[1].The numerical results reveal that our new SPH approach using inverse logarithmic kernel function outper-forms existing ones in particle restoration,zero error,better accuracy and enhanced efficiency in kernel *** new kernel function showed some improvement over existing kernels by showing very less error approximation value of 0.035h *** results showed some improvements over standard technique by being capable of handling problems with large deformations accurately and precisely.

关键词： Inverse logarithmic function Moving least squares approximation Shock wave propagation 3D dam-break flow Zero error

Laser induced photo-detachment of O2 in DC discharge

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Plasma Science and Technology 2018年第7期20卷 98-105页

作者： j r legorreta j l patiNo f b yousif Centro de Investigacion en Ciencias Universidad Autonoma del Estado de Morelos.Av.UniversidadNo.1001 Col.Chamilpa Cuemavaca MorelosMexico

Determination of the negative ion number density of O2 and O in a DC discharge of oxygen plasma was made employing Langmuir probe in conjunction with eclipse laser photo- detachment technique. The temporal evolution of the extra electrons resulting from the photo- detachment of O2- and O- were used to evaluate the negative ion number density. The ratio of O2 number density to O varied from 0.03 to 0.22. Number density of both O~ and O increased with increasing power and decreased as the pressure was increased. Electron number density was evaluated from the electron energy distribution function （EEDF） using the I-V recorded characteristic curves. Electron temperature between 2 and 2.7 eV were obtained. Influence of the 02（al△g） metastable state is discussed.

关键词： electronegative plasma electron temperature Langmuir probe negative ion number density