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Numerical analysis of the effects of vesicle distribution characteristics on the engineering properties of volcanic rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第12期15卷 3094-3104页

作者： P.l.P.Wasantha Z.Heng t.Xu College of Sport Health and EngineeringVictoria UniversityMelbourneVIC3011Australia Institute for Sustainable Industries and liveable Cities Victoria UniversityMelbourneVIC3011Australia Center for Rock Instability and Seismicity Research Northeastern UniversityShenyang110819China

Vesicles can be of different sizes and shapes and can be randomly distributed within vesicular volcanic rocks. this study investigates the variation of engineering properties of vesicular rocks due to the changes in vesicle distribution characteristics for different cases of bulk porosity and vesicle diameter using a systematic numerical simulation program using the finite element method-based rock failure process analysis (RFPA) software. Models with uniform-size vesicles and combinations of different proportions of different-sized vesicles were considered to resemble natural vesicular rocks more closely, and ten different random vesicle distributions were tested for each case. Increasing bulk porosity decreased the uniaxial compressive strength (UCS) and elastic modulus of the specimens, and the specimens with the lowest bulk porosity showed the greatest range of UCS values in the case of uniform-size vesicles. the effect of vesicle diameter on UCS showed an unsystematic response which was understood to be a result of different vesicle distribution patterns, some of which facilitated a shear failure. Specimens with multiple-size vesicles in different proportions revealed that the variation of UCS due to vesicle distribution characteristics is minimum when the bulk porosity is equally shared by different size vesicles. In addition, when the proportion of smaller-sized vesicles is higher, UCS showed an increase compared to that of the equal proportion of different size vesicles case at low porosities, but a decrease at higher porosities. Variation of elastic modulus showed minor, unsystematic fluctuations as a function of vesicle diameter and different proportions of different-sized vesicles, and the range for different vesicle distribution patterns was narrow in general. Overall, the findings of this study recommend cautious use of the engineering properties determined through a limited number of laboratory tests on vesicular rocks.

关键词： Vesicular rocks Porosity Vesicle size and distribution Numerical simulation Mechanical characteristics

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Microstructure of Nitrided Aluminum Alloys Using an Electron-Beam-Excited-Plasma (EBEP)

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材料热处理学报 2004年第5期25卷 349-353页

作者： l.liu A.Yamamoto t.Hishida H.Shoyama t.Hara H.tsubakino GraduateSchool UniversityofHyogo2167ShoshaHimeji671-2201Japan FaultyofEngineering ToyotaTechnologicalInstituteNagoya468-8511Japan

Nitriding of surface of aluminum alloys was carried out with using an electron-beam-excited-plasma (EBEP) technique. the EBEP is sustained by electron impact ionization with energetic electron beam. two kinds of substrates, aluminum alloys AA5052 and AA5083, were exposed to the down flow of EBEP source at 843 K for 45min. the specimens were characterized with respect to following properties: crystallographic structure (XRD), morphology (SEM) and the cross sectional microstructures of the nitrided layer was observed using a scanning electron microscopy (SEM). there are some A12O3 particles on the surface of the nitrided AA5052 and AA5083. the A1N layers were formed on the substrates with the thickness of 4.5 fi m for AA5052 and 0.5 /z m for AA5083 . A relatively uniform nitrided surface layer composed of A1N can be observed on the AA5052 substrate. the grains size near the interfaces between the substrate and A1N layer were smaller than that near the surface. On the surface of A1N layer, the concentration of nitrogen was high and in the middle of A1N layer it had a constant concentration like the aluminum and the concentration was decreased with approaching to the interface. On the surface of nitrided AA5083, a uniform A1N layer was not formed as the reason for the high nitriding temperature.

关键词：显微结构铝合金渗氮 EBEP

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Prediction of the flooding area of the northeastern Caspian Sea from satellite images

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Geodesy and Geodynamics 2023年第2期14卷 191-200页

作者： Anzhelika t.Kamza Irina A.Kuznetsova Eugene l.levin Satbayev University Almaty 050013Kazakhstan limited partnership"International Educational Corporation" Almaty 050043Kazakhstan School of Applied Computational Sciences Meharry Medical CollegeTennessee 37208USA

Studying the dynamic changes in the coastline of the northeastern Caspian Sea is significant since the level of the Caspian is unstable,and the coastline change can cause enormous damage to the ecology,economy,and population of the coastal part of *** this work,we use remote sensing and Geographic Information System(GIS)technologies to study the changes in the coastline of the northeastern Caspian Sea and predict the extent of flooding with increasing water *** proposed methodology for creating dynamic maps can be used to monitor the coastline and forecast the extent of flooding in the *** a result of this work,the main factors affecting changes in the coastline were *** analyzing the water level data from 1988 to 2019,it was revealed that the rise in water level was observed from 1980 to *** maximum sea level rise was recorded at-26.04 *** that,the sea level began to fall,and between 1996 and 2009,there were no significant changes;the water level fluctuated with an average of-27.18 ***,a map of the water level dynamics in the Caspian Sea from 1988 to 2019 was *** to the dynamics map,water level rise and significant coastal retreat were revealed,especially in the northern part of the Caspian Sea and the northern and southern parts of Sora *** method for predicting the estimated flooding area was *** a result,based on a single map,the flooding area of the northeast coast was predicted.A comparative analysis of landsat and SRtM data is presented.

关键词： Caspian Sea Seabed Earth remote sensing GIS landsat Prediction of the flooding area Ecology of coastline SRtM

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li(2p←2s)+Na(3s)pressure broadening in the far-wing and line-core profiles

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Chinese Physics B 2022年第7期31卷 247-254页

作者： F talbi N lamoudi l Reggami M t Bouazza K Alioua M Bouledroua Physics Department Badji Mokhtar UniversityB.P.12Annaba 23000Algeria laboratoire de Physique des Rayonnements Badji Mokhtar UniversityB.P.12Annaba 23000Algeria laboratoire d’Etude des Surfaces et Interfaces de la Matiere Solide(lESIMS) Badji Mokhtar UniversityB.P.12 Annaba 23000Algeria laboratoire lAMA Laboratoire des Materiaux Avances(LAMA)Badji Mokhtar UniversityB.P.12 Annaba 23000Algeria laboratoire de Physique de la Matiere et du Rayonnement lPMR Universite Cherif MessaidiaB.P.1553Souk-Ahras 41000Algeria

this work reports pressure-broadening line-wing and line-core of the lithium li(2p←2s)resonance line perturbed by ground sodium Na(3s)*** far-wing regions,the calculations are performed quantum-mechanically and are intended to examine the photoabsorption coefficients at diverse *** results show the existence of three satellites,in the blue wing near the wavelengths 470 nm and in the red wing around 862 nm and 1070 *** the line-core region,by adopting the simplified Baranger model,the line-width and line-shift rates are determined,and their variation law with temperature is *** published data were found to compare these results with.

关键词： pressure broadening line-core broadening far-wing spectra photoabsorption

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Daddy darling——the synopsis of

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语言教育 1997年第5期 36-37页

作者： Carol thatcher 李立欣

three women,as far as is known,captured Denis thatcher’sheart:the famous Margaret,his first wife Margot,and his daugh-ter *** these,Carol must be the most *** is notto say anything against Margare,a dutiful wife who ... 详细信息

关键词： anything Margaret captured Carol daughter father Daddy darling really women 卡罗尔

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Student Conceptions of Assessment:Regulatory Responses to Our Practices

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ECNU Review of Education 2022年第1期5卷 116-139页

作者： Gavin t.l.Brown Development&Professional Practice The Faculty of Education and Social WorkThe University of AucklandPrivate Bag 92019Victoria Street WestAuckland 1142New Zealand

Purpose:Universities assess and evaluate students concerning competence in essential disciplinary knowledge and *** assessments impact learners’attitudes,beliefs,and *** impacts may be overcome if students regulate their responses to assessment and ***/Approach/Methods:this article systematically locates research studies that cite three key early papers around student conceptions of assessment(SCoA).A narrative synthesis is based on 22 ***:In addition to the SCoA,11 different research inventories reveal a variety of regulatory responses that are enhanced when assessments are deliberately formative,fair,and *** is broad interest in this phenomenon but little consistency in methods,and even the SCoA has little consistency in factor structure across *** one study provided an objective behavioral measure to validate self-reports,which are the dominant form of ***/Value:this review gives readers insights into how assessment influences student thinking and how student cognition can regulate success.

关键词： Conceptions of assessment higher education learners self-regulated learning

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Enhanced urban functional land use map with free and open-source data

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International Journal of Digital Earth 2021年第11期14卷 1744-1757页

作者： t.t.Vu N.V.A.Vu H.P.Phung l.D.Nguyen Faculty of Engineering and Science Curtin University MalaysiaMiriMalaysia Vietnam National Space Center Vietnam Academy of Science and Technology(VAST)Ho Chi Minh cityVietnam

the study aims at developing an applicable methodology to produce the functional land-use map using only free and open-source ***-view Sentinel image and ground-view Open Street Map(OSM)data are chosen due to their extensive *** three-stage framework,including object-based image analysis,OSM data cleaning,and ontology-based decision fusion,is proposed and implemented with open-source *** applied the developed approach to districts 1,4,and 7 of HoChiMinh city,representing the complexities of the dynamic change in big *** result showed a good functional land use map with 78.70%overall *** outcome presents the mismatch between the data-driven approach and human knowledge,which can be improved by ontology-based fusion with OSM *** ontology-based framework comprises the common urban land-use classes and OSM attributes,which can be applied and extended in other urban *** text attributes may be applicable only locally and can be modified in our open-source ***-based image analysis takes advantage of Google Earth Engine computing power,whereas ontology-based processing works well on a local *** future studies,adopted natural language processing to pre-process OSM data and ontology-based fusion will be implemented on the cloud-computing platform to enhance computational efficiency.

关键词： Data fusion Remote Sensing Digital City land use GIS

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Geomechanical characterization of volcanic rocks using empirical systems and data mining techniques

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 138-150页

作者： t.Miranda l.R.Sousa A.t.Gomes J.tinoco C.Ferreira University of Minho GuimarasPortugal State Key laboratory of Geomechanics and Deep Underground Engineering China University of Mining and TechnologyBeijingChina University of Porto PortoPortugal

this paper tries to characterize volcanic rocks through the development and application of an empirical geomechanical system. Geotechnical information was collected from the samples from several Atlantic Ocean islands including Madeira, Azores and Canarias archipelagos. An empirical rock classification system termed as the volcanic rock system(VRS) is developed and presented in detail. Results using the VRS are compared with those obtained using the traditional rock mass rating(RMR) system. Data mining(DM) techniques are applied to a database of volcanic rock geomechanical information from the *** algorithms were developed and consequently approaches were followed for predicting rock mass classes using the VRS and RMR classification systems. Finally, some conclusions are drawn with emphasis on the fact that a better performance was achieved using attributes from VRS.

关键词： Volcanic rocks Geomechanical characterization Volcanic rock system(VRS) Data mining(DM)

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Old dogs with new tricks:intra-axonal translation of nuclear proteins

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Neural Regeneration Research 2015年第10期10卷 1560-1562页

作者： Jeffery l.twiss tanuja t.Merianda Department of Biological Sciences University of South Carolina Department of Neurobiology and Anatomy Drexel University College of Medicine

Many different types of polarized eukaryotic cells have been shown to segregate synthesis for some protein subpopulations to cytoplasmic domains distant from their *** neurons,these distances can be tens-to-thousands ... 详细信息

关键词： HMGN Old dogs with new tricks RNA

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Precision livestock Farming: Precision feeding technologies and sustainable livestock production

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International Journal of Agricultural and Biological Engineering 2012年第4期5卷 54-61页

作者： t M Banhazi l Babinszky V Halas M tscharke National Centre for Engineering in Agriculture University of Southern QueenslandToowoombaQueensland4350 Australia Department of Feed and Food Biotechnology University of DebrecenH-4015 DebrecenHungary Department of Animal Nutrition Kaposvár UniversityH-7400 KaposvárHungary PlF Agritech Pty.ltd.Queensland 4350 Australia

In order to be able to produce safe,uniform,cheap,environmentally-and welfare-friendly food products and market these products in an increasingly complex international agricultural market,livestock producers must have access to timely production related *** the information related to feeding/nutritional issues is important,as feeding related costs are always significant part of variables costs for all types of livestock ***,automating the collection,analysis and use of production related information on livestock farms will be essential for improving livestock productivity in the ***-controlled livestock production systems with an information and communication technology(ICt)focus are required to ensure that information is collected in a cost effective and timely manner and readily acted upon on *** electronic and ICt related technologies introduced on farms as part of Precision livestock Farming(PlF)systems will facilitate livestock management methods that are more responsive to market *** PlF technologies encompass methods for electronically measuring the critical components of the production system that indicate the efficiency of resource use,interpreting the information captured and controlling processes to ensure optimum efficiency of both resource use and livestock *** envisaged real-time monitoring and control systems could dramatically improve production efficiency of livestock ***,further research and development is required,as some of the components of PlF systems are in different stages of *** addition,an overall strategy for the adoption and commercial exploitation of PlF systems needs to be developed in collaboration with private *** article outlines the potential role PlF can play in ensuring that the best possible management processes are implemented on farms to improve farm profitability,quality of products,welfare of livestock and

关键词： Precision livestock Farming(PlF) precision feeding control systems automation software-based technology sensors nutrition pig farm

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