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World Journal of Diabetes 2017年第1期8卷 18-27页

作者： Kristina s petersen Jennifer B Keogh peter J Meikle Manohar L Garg peter M Clifton school of Pharmacy and Medical sciences University of South Australia Baker IDI Heart and Diabetes Institute Nutraceuticals Research Group University of NewcastleCallaghan

AIM To determine the clinical and dietary predictors of common carotid artery intima media thickness(CCA IMT) in a cohort of subjects with type 1 and type 2 diabetes. METHODs Participants with type 1(n = 23) and type 2 diabetes(n = 127) had mean and mean maximum CCA IMT measured using B mode ultrasound. Dietary intake was measured using a food frequency questionnaire. Clinical and dietary predictors of mean and mean maximum CCA IMT were determined using linear regression analysis adjusted for potential confounders. REsULTs The main predictors of mean and mean maximum CCA IMT were age and weight. After multivariate adjustment there were no dietary predictors of CCA IMT. However,in subjects that were not prescribed a lipid lowering medication alcohol consumption was positively associated with CCA IMT after multivariate adjustment. No difference existed in CCA IMT between subjects with type 1 or type 2 diabetes once age was adjusted for. CONCLUsION CCA IMT was predominantly predicted by age and weight in these subjects with diabetes. The finding that CCA IMT was not different between people with type 1 and type 2 diabetes warrants further investigation in a larger cohort.

关键词： Diabetes Carotid intima media thickness Arterial structure Diet Lipidomics Carotenoids

Experimental investigation on slip conditions during thread rolling with flat dies

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Friction 2024年第1期12卷 136-143页

作者： stefan VOLZ peter GROCHE Institute for Production Engineering and Forming Machines Technical University DarmstadtOtto-Berndt Straße 2Darmstadt 64287Germany

The process design of flat die rolling operations can be a tedious and costly process due to the challenges posed by small process *** this work,an effort is made to closely investigate and understand the process limits caused by excessive slippage of the *** measurements are carried out to capture the characteristics of excessive slippage and the influence of the stroke rate and the tribological system on this process *** differences in slippage were observed,depending on the tribological *** systems with polymer based lubricants showed excessive slippage at low stroke rates,systems using oil or no lubricant endured higher stroke rates before process limits were *** optical measurements revealed three major forms of slippage:successful rolling without slippage,failure due to excessive slippage at process start,and failure due to excessive slippage at around one workpiece rotation.

关键词： rolling incremental forming thread rolling slippage profile rolling

“Towards Re-Inventing Psychohistory”:Predicting the Popularity of Tomorrow’s News from Yesterday’s Twitter and News Feeds

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Journal of systems science and systems Engineering 2021年第1期30卷 85-104页

作者： Jiachen sun peter Gloor MIT Center for Collective Intelligence 245 First StreetCambridgeMA02142USA school of Electronics and Information Technology Sun Yat-Sen UniversityGuangzhou510275China

Rapid advances in machine learning combined with wide availability of online social media have created considerable research activity in predicting what might be the news of tomorrow based on an analysis of the *** this work,we present a deep learning forecasting framework which is capable to predict tomorrow’s news topics on Twitter and news feeds based on yesterday’s content and topic-interaction *** proposed framework starts by generating topics from words using word embeddings and K-means *** temporal topic-networks are constructed where two topics are linked if the same user has worked on both *** and dynamic metrics calculated from networks along with content features and past activity,are used as input of a long short-term memory(LsTM)model,which predicts the number of mentions of a specific topic on the subsequent *** dependencies among topics,our experiments on two Twitter datasets and the HuffPost news dataset demonstrate that selecting a topic’s historical local neighbors in the topic-network as extra features greatly improves the prediction accuracy and outperforms existing baselines.

关键词： Topic’s popularity trend forecasting social media

Genetic climatic regionalization of the Balkan Peninsula using cluster analysis

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Journal of Geographical sciences 2017年第1期27卷 43-61页

作者： peter NOJAROV National Institute of Geophysics Geodesy and Geography Bulgarian Academy of Sciences Akad. G. BonchevStr. BI.3 Room 327 1113 Sofia Bulgaria

sea Level Pressure（sLP） data for the period 1950–2012 at 61 stations located in or around the Balkan Peninsula was used. The main concept is that intra-annual course of sLP represents the best different air masses that are situated over the Balkan Peninsula during the year. The method for differentiation of climatic zones is cluster analysis. A hierarchical clustering technique–average linkage between groups with Pearson correlation for measurement of intervals was employed in the research. The climate of the Balkan Peninsula is transitional between oceanic and continental and also between subtropical and temperate climates. several major changes in atmospheric circulation over the Balkan Peninsula have happened over the period 1950–2012. There is a serious increase of the influence of the Azores High in the period January–Marchwhich leads to an increase of sLP and enhances oceanic influence. There is an increase of the influence of the north-west extension of the monsoonal low in the period June–september. This leads to more continental climatebut also to more tropical air masses over the Balkan Peninsula. Accordinglythe extent of subtropical climate widens in northern direction. There is an increase of the influence of the siberian High in the period October–December. This influence covers central and eastern part of the peninsula in October and Novemberand it reaches western parts in December. Thusthe climate becomes more continental.

关键词： genetic classification regionalization Balkan Peninsula cluster analysis sea Level Pressure circulation indices

Hypervelocity Impacts and Exposed Lithospheric Mantle: A Way to Recognize Large Terrestrial Impact Basins?

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Journal of Earth science 2019年第3期30卷 451-459页

作者： peter Olds Chemistry Faculty College of Alameda

On the Moon and Mars olivine of probable mantle origin is detected at rims of large Late Heavy Bombardment(LHB) age impact basins for which excavation depth estimates exceed crustal thickness estimates. But lunar Crisium size impact basins are not recognized on Earth nor expected in the Phanerozoic from conventional interpretations of crater size frequency distributions. In this study several large circular to elliptical basin structures on Earth, for which hypothesized impact excavation depth would greatly exceed crustal thickness, are examined for the presence of exposed lithospheric mantle, expressed as ophiolite, at the rims. Three Phanerozoic impact basins, modified by plate tectonics and tentatively correlated with "ophiolite obduction" plus global extinction events, are proposed here. These tentatively suggested Phanerozoic impact basins are:(1) Yucatan Basin/Puerto Rico Trench with a Greater Antilles ophiolite rim. Cretaceous-Paleogene Boundary global extinction may correlate with Maastrichtian ophiolite obduction in southeast Cuba.(2) Loyalty Basin with a New Caledonia ophiolite plus d’Entrecasteaux Ridge rim. Late Eocene global extinction may correlate with obduction of the New Caledonia Peridotite Nappe.(3) sulu sea Basin with a Palawan, sabah etc. ophiolite rim. The Middle Miocene Disruption Event may correlate with ophiolite obduction plus ophiolitic mélange emplacement in sabah and in Palawan. These originally circular to elliptical belts of exposed lithospheric mantle may serve as strain markers for relative plate motions in the vicinity of plate boundaries during post-impact geologic times. It is further speculated that plate boundaries may be initiated and/or modified by such impacts.

关键词： olivine mantle impact basin ophiolite obduction mass extinction

Nonlocal Nonlinear Advection-Diffusion Equations

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Chinese Annals of Mathematics,series B 2017年第1期38卷 281-292页

作者： peter CONsTANTIN Department of Mathematics Princeton UniversityPrincetonNJ 08544USA.

The author reviews some results about nonlocal advection-diffusion equations based on lower bounds for the fractional Laplacian.

关键词： Nonlocal Advection Diffusion Fractional Laplacian

Generic principles of crack-healing ceramics

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Journal of Advanced Ceramics 2012年第4期1卷 249-267页

作者： peter GREIL Department of Materials science(Glass and Ceramics) University of Erlangen-NuernbergMartensstr.5Erlangen 91058Germany

Ceramic materials able to heal manufacture or damage induced microstructure defects might trigger a change in paradigm for design and application of load bearing *** work reviews thermodynamic and kinetic aspects governing the regeneration of solid contact able to transfer stress between disrupted crack surfaces in *** crack healing processes include perturbation of crack-like pores followed by sintering of isolated pores,as well as reaction with an environmental atmosphere and filling of the crack space with an oxidation *** thermally activated solid state reactions require elevated temperatures which may exceed 1000℃,processes able to trigger crack healing at lower temperatures are of particular interest for transferring into engineering *** principles of microstructure modifications able to facilitate crack repair at lower temperatures will be considered:(i)acceleration of material transport by grain boundary decoration and grain size reduction,and(ii)reduction of thermal activation barrier by repair filler *** demonstrating crack healing capability include oxidation reaction of low energy bonded intercalation metal from nano-laminate MAX phases and catalyzed surface nitridation of polymer derived ceramics containing repair fillers.

关键词： crack healing microstructure modifications oxidation healing MAX phases preceramic polymers

Changes in Air Temperatures and Atmosphere Circulation in High Mountainous Parts of Bulgaria for the Period 1941-2008

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Journal of Mountain science 2012年第2期9卷 185-200页

作者： peter NOJAROV National Institute of Geophysics Geodesy and GeographyBulgarian Academy of Sciences

Changes of air temperatures and atmosphere circulation at three high mountainous stations in Bulgaria are investigated for the period of *** three stations are located on peaks Musala,Cherni vrah and Botev,where air temperature data have good *** missing data were recovered using the method of differences. A significant mean annual air temperature rise happened in high mountainous parts of Bulgaria- the warming is in the order of 0.7°C for the entire *** increase is very prominent particularly in the last 30 *** contributors to this overall tendency are summer months-June,July and *** some degree,January also could be included in this *** trend shows temperature rise at the beginning of the investigated *** of the causes for such a tendency is atmosphere circulation in respective *** also shows signs of considerable reorganization in both winter and *** is an increase of the cases of warm atmosphere patterns typical for winter, summer and autumn seasons in *** circulation has essential significance for air temperatures during the cold half of the *** January and June atmosphere circulation has a substantial influence on the thermal regime of air in high mountains of *** July,August and November this influence is *** are no cycles in air temperatures for the investigated period.

关键词： Air temperature Trends Atmosphere circulation Bulgaria Mountains

Counter Rotating Fans- An Aircraft Propulsion for the Future?

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Journal of Thermal science 2003年第2期12卷 97-103页

作者： peter schimming DLR Institute for Propulsion TechnologyCologneGermany

In the mid seventies a new propulsor for aircraft was designed and investigated - the so-called PROPFAN. With regard to the total pressure increase, it ranges between a conventional propeller and a turbofan with very high bypass ratio. This new propulsion system promised a reduction in fuel consumption of 15 to 25% compared to engines at that time.A lot of propfans (Hamilton standard, UsA) with different numbers of blades and blade shapes have been designed and tested in wind tunnels in order to find an optimum in efficiency, Fig.1. Parallel to this development GE, UsA, made a design of a counter rotating unducted propfan, the so-called UDF, Fig.2. A prototype engine was manufactured and investigated on an in-flight test bed mounted at the MD82 and the B727. since that time there has not been any further development of propfans (except AN 70 with NK 90-engine, Ukraine, which is more or less a propeller design) due to relatively low fuel prices and technical obstacles. Only technical programs in different countries are still going on in order to prepare a data base for designing counter rotating fans in terms of aeroacoustics, aerodynamics and aeroelasticities. In DLR, Germany, a lot of experimental and numerical work has been undertaken to understand the physical behaviour of the unsteady flow in a counter rotating fan.

关键词： propfan counter rotation unsteady aerodynamics active noise control aeroelasticities.

Homogenization of Reynolds Equation by Two-scale Convergence

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Chinese Annals of Mathematics,series B 2007年第3期28卷 363-374页

作者： peter WALL Department of Mathematics Lule University of TechnologyS-971 87 Lule Sweden.

To increase the hydrodynamic performance in different machine elements, as e.g. journal bearings and thrust bearings, during lubrication it is important to understand the influence of surface roughness. In this connection one encounters homogenization of the incompressible Reynolds equation, where the roughness of the lubricated surface is assumed to be periodic. This problem has recently been studied in more engineering- oriented papers by using the formal method of multiple scale expansion. In this paper, we rigorously prove both homogenization and corrector results by using two-scale convergence, which may be regarded as a justification of the formal multiple scale expansion method described above. Moreover, some numerical illustrations and results are presented.

关键词： Homogenization Two-scale convergence Reynolds equation Lubrication