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Visualising data distributions with kernel density estimation and reduced chi-squared statistic

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Geoscience Frontiers 2017年第6期8卷 1247-1252页

作者： c.J.Spencer c.Yakymchuk m.Ghaznavi Earth Dynamics Research Group The Institute of Geoscience ResearchDepartment of Applied GeologyCurtin UniversityPerthAustralia Department of Earth and Environmental Sciences University of WaterlooWaterlooCanada David R.cheriton School of computer Science University of WaterlooWaterlooCanada

The application of frequency distribution statistics to data provides objective means to assess the nature of the data distribution and viability of numerical models that are used to visualize and interpret *** commonly used tools are the kernel density estimation and reduced chi-squared statistic used in combination with a weighted *** to the wide applicability of these tools,we present a Java-based computer application called KDX to facilitate the visualization of data and the utilization of these numerical tools.

关键词： Data visualisation Kernel density estimation Reduced chi-squared statistic mean square weighted deviation Geostatistics

A Grid middleware for Distributed Java computing with mPI Binding and Process migration Supports

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Journal of computer Science & Technology 2003年第4期18卷 505-514页

作者：陈琳王卓立 Francis c.m.Lau Department of computer Science and Information Systems The University of Hong Kong P.R. China

"Grid" computing has emerged as an important new research field. With years of efforts, grid researchers have successfully developed grid technologies including security solutions,resource management protocols, information query protocols, and data management services. However, as the ultimate goal of grid computing is to design an infrastructure which supports dynamic,cross-organizational resource sharing, there is a need of solutions for efficient and transparent task re-scheduling in the *** this research, a new grid middleware is proposed, called G-JavamPI. This middleware adds the parallel computing capability of Java to the grid with the support of a Grid-enabled message passing interface (mPI) for inter-process communication between Java processes executed at different grid points. A special feature of the proposed G-JavamPI is the support of Java process migration with post-migration message redirection. With these supports, it is possible to migrate executing Java process from site to site for continuous computation, if some site is scheduled to be turned down for system reconfiguration. moreover, the proposed G-JavamPI middleware is very portable since it requires no modification of underlying OS, Java virtual machine, and mPI package. Preliminary performance tests have been conducted. The proposed mechanisms have shown good migration efficiency in a simulated grid environment.

关键词： grid middleware mPI Java process migration

Hot cracking in AZ31 and AZ61 magnesium Alloy

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Journal of materials Science & Technology 2011年第7期27卷 633-640页

作者： c.J. Huang c.m. cheng c.P. chou F.H. chen Department of mechanical Engineering National Chiao Tung University Hsinchu 300 Taiwan China Department of Industrial Education National Taiwan Normal University Taipei 106 Taiwan China

This paper examined the impact of the number of thermal cycles and augmented strain on hot cracking in AZ31 and AZ61 magnesium alloy. Statistical analyses were performed. Following observation using a scanning electron microscope （SEm）, an energy dispersive spectrometer （EDS） was used for component analysis. Results showed that Al content in magnesium alloy has an effect on hot cracking susceptibility. In addition, the nonequilibrium solidification process produced segregation in Al content, causing higher liquid mg-alloy rich Al content at grain boundaries, and resulting into liquefied grain boundaries of partially melted zone （PmZ）. In summary, under multiple thermal cycles AZ61 produced serious liquation cracking. AZ61 has higher （6 wt%） Al content and produced much liquefied mg17Al12 at grain boundaries under multiple thermal cycles. The liquefied mg17Al12 were pulled apart and hot cracks formed at weld metal HAZ due to the augmented strain. Since AZ31 had half the Al content of AZ61, its hot-cracking susceptibility was lower than AZ61. In addition, AZ61 showed longer total crack length （TcL） in one thermal cycle compared to that in three thermal cycles. This phenomenon was possibly due to high-temperature gasification of Al during the welding process, which resulted in lower overall Al content. consequently, shorter hot cracks exhibited in three thermal cycles. It was found the Al content of AZ31 and AZ61 can be used to assess the hot-cracking susceptibility.

关键词： Varestraint test Thermal cycles Hot-cracking susceptibility Gas tungsten arc welding (GTAW) AZ31 AZ61

chemical forms and extractability of iron in sediments of three contrasting lakes of china and UK

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Journal of Environmental Sciences 2003年第6期15卷 728-733页

作者： Gibson c.E.,Stewart B.m. Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology chinese Academy of Sciences Department of Agricultural and Environmental Science Queen's University Belfast Shenyang 110016 china Newforge Lane Belfast BT9 5PX UK

Iron is a limiting factor for the eutrophication of lakes, especially those lakes that are enriched with phosphorus. Extractability of iron in sediments of West Lake and Taihu Lake in china and Lower Lough Erne in Northern Ireland of UK was comparatively investigated on the basis of analysing chemical forms of iron using different extractants. It was shown that extractable iron in sediments of the lakes was greatly different using various extractants. Reactive iron or easily released iron such as “active" iron oxides, total free iron oxide and water-soluble iron was not high, only accounting for 0.01%—0.15% of total iron. The efficiency of the extractants for exchangeable iron was decreased in the sequence 0.1 mol/L Hcl DTPA+TEA mixed solution > 1 mol/L NH 4OAc > 0.5 mol/L mgcl 2 = 0.5 mol/L cacl 2. It seems that the complexion of iron by organic matter was not strong because the concentration of organically bound iron was significantly lower than the concentration it was forecasted. Extractable iron is not entirely consistent with or dependent on total iron in lake sediments. To a certain extent, phosphate can inhibit the release of iron in sediments of the lakes. The selection of extractants is thus the first key step to evaluate bioavailability of iron in lake sediments.

关键词： iron chemical form extractability lake sediment eutrophication

Hear no evil： The effect of auditory warning signals on avian innate avoidance, learned avoidance and memory

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current Zoology 2011年第2期57卷 197-207页

作者： Emma c. SIDDALL Nicola m. mARPLES School of Natural Sciences Trinity College Dublin Dublin 2 Ireland

many aposematic insect species advertise their toxicity to potential predators using olfactory and auditory signals, in addition to visual signals, to produce a multimodal warning display. The olfactory signals in these displays may have interesting effects, such as eliciting innate avoidance against novel colored prey, or improving learning and memory of defended prey. However, little is known about the effects of such ancillary signals when they are auditory rather than olfactory. The few studies that have investigated this question have provided conflicting results. The current study sought to clarify and extend understanding of the effects of prey auditory signals on avian predator responses. The domestic chick Gallus gallus domesticus was used as a model avian predator to examine how the defensive buzzing sound of a bumblebee Bombus terrestris affected the chick＇s innate avoidance behavior, and the learning and memory of prey avoidance. The results demonstrate that the buzzing sound had no effect on the predator＇s responses to unpalatable aposematically colored crumbs, suggesting that the agitated buzzing of B. terrestris may provide no additional protection from avian predators .

关键词： Aposematism Auditory signals Dietary conservatism Avoidance learning memorability multimodal signaling

Analysis of electron energy distribution function in a magnetically filtered complex plasma

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chinese Physics B 2013年第4期22卷 324-329页

作者： m K Deka H Bailung N c Adhikary Physical Sciences Division Institute of Advanced Study in Science and Technology Vigyan Path Paschim Boragaon Garchuk Guwahati-781035 Assam India

The electron energy distribution function （EEDF） for a magnetically filtered dusty plasma is studied in a dusty double plasma device where the electron energy can be varied from 0.15 eV to ～ 2.8 eV and plasma density from 10 6 cm-3 to 10 9cm-3 . The characteristics of EEDF for these ranges of plasma parameters are investigated in a pristine plasma as well as in a dusty plasma. The results show that in the presence of dust, there is a drastic modification in EEDF patterns in a plasma with higher electron temperature and density than those in a low temperature and low density plasma produced by the magnetic filter.

关键词： dusty plasma magnetic filter electron energy distribution function

OH and O radicals production in atmospheric pressure air/Ar/H_2O gliding arc discharge plasma jet

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Plasma Science and Technology 2017年第12期19卷 71-80页

作者： N c ROY m R TALUKDER A N cHOWDHURY Plasma Science and Technology Laboratory Department of Applied Physics and Electronic EngineeringUniversity of RajshahiRajshahi 6205Bangladesh Bangladesh council of Scientific and Industrial Research Laboratory Rajshahi Rajshahi 6206Bangladesh

Atmospheric pressure air/Ar/H_2O gliding arc discharge plasma is produced by a pulsed dc power supply. An optical emission spectroscopic（OES） diagnostic technique is used for the characterization of plasmas and for identifications of OH and O radicals along with other species in the plasmas. The OES diagnostic technique reveals the excitation Tx？≈？5550–9000 K, rotational Tr？≈？1350–2700 K and gas Tg？≈？850–1600 K temperatures, and electron density n？（1.1-1.9） ′101 4 cm^（-3） e under different experimental conditions. The production and destruction of OH and O radicals are investigated as functions of applied voltage and air flow rate. Relative intensities of OH and O radicals indicate that their production rates are increased with increasing Ar content in the gas mixture and applied voltage. nereveals that the higher densities of OH and O radicals are produced in the discharge due to more effective electron impact dissociation of H_2O and O_2 molecules caused by higher kinetic energies as gained by electrons from the enhanced electric field as well as by enhanced n *** productions of OH and O are decreasing with increasing air flow rate due to removal of Joule heat from the discharge region but enhanced air flow rate significantly modifies discharge maintenance properties. Besides, Tgsignificantly reduces with the enhanced air flow rate. This investigation reveals that Ar plays a significant role in the production of OH and O radicals.

关键词： reactive oxygen species(ROS) optical emission spectroscopy(OES) gliding arc discharge plasma kinetics broadening mechanism

Spent coffee grounds as a renewable source of energy: An analysis of bulk powder flowability

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Particuology 2019年第2期17卷 92-100页

作者： L. massaro Sousa m.c. Ferreira Drying center for Pastes Suspensions and Seeds. Chemical Engineering Department Federal University of Sao Carlos. P.O. Box 676 13565-905 Sao Carlos Brazil

The main use for spent coffee grounds (ScG) produced in the soluble coffee industry is thermal energy generation in the industry itself. The ScG are processed using operations that are strongly dependent on powder flow behavior. In this study, we evaluated two classical flowability in dices of non-consolidated ScG powders: the angle of repose (AoR), and the Hausner ratio (HR). The influences of the mean particle diameter, particle size distribution (PSD), and water content on the AoR and HR values of ScG were analyzed for powders with a mean particle size range of 225-550 μm. For powders with a mean particle size close to 350 μm and for mixtures containing more than 40% fine particles, the HR (>1.35) and AoR (>45 °) values were characteristic of poor flowability. The AoR was sensitive to the powder PSD, and powders with similar mean particle sizes had higher AoR values when the PSD was larger. For powders w让h water contents up to 50%, the flowability indices were not greatly affected by the water content. A modified linear-mixture packing model was used to predict the packed bed void fractions for binary and ternary mixtures of the three base powders. The model was used to construct a ternary diagram to estimate the HR values of the mixtures. An equation was fitted to correlate HR and AoR. The proposed diagram and the equation provide insight into flow behavior and could be used for process design of industrial plants that handle ScG.

关键词： Spent coffee ground Biomass Flowability Hausner ratio Angle of repose

The effect of pyrazine odor on avoidance learning and memory in wild robins Erithacus rubecula

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current Zoology 2011年第2期57卷 208-214页

作者： Emma c. SIDDALL Nicola m. mARPLES School of Natural Sciences Trinity College Dublin Dublin 2 Ireland

Toxic insects advertise their defended state to potential predators using warning displays. Frequently these displays use cues through more than one sensory modality, and combine color, smell and sound to produce a multimodal warning display. Signalling through more than one sensory pathway may enhance the rate of avoidance learning, and the memorability of the learned avoidance. A common insect warning odor, pyrazine, has previously been shown to increase the rate of learned avoidance of unpalatable yellow prey by domestic chicks （GaUus gallus domesticus）, and the odor also improved memory of this learned avoidance. However, to date no research has examined this response to pyrazine odor using wild birds under natural conditions. This study used wild robins （Erithacus rubecula） to investigate whether wild birds avoided yellow baits that smelled of pyrazine more strongly than those presented with no odor. The results provide some evidence that pyrazine odor does increase the level of protection an aposematic insect gains from a wild avian predator, but that the effect of pyrazine on learned avoidance was much weaker than was found with domestic chicks .

关键词： Aposematism Learned avoidance memory multimodal warning display Pyrazine Robins