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GIS-based optimisation of the hydrometeorological network in Greece

1992年

作者： m.e.·法耶德(m.e. Fayed) L.·阿腾(L. Otten)

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International Journal of Digital earth 2009年第2期2卷 171-185页

作者： e.A.Baltas m.A.mimikou Department of Hydraulics Soil Science and Agricultural EngineeringSchool of AgricultureAristotle University of Thessaloniki54006Greece Department of Water Resources and environmental engineering National Technical University of AthensGreece

The operation of a network of hydrometeorological stations constitutes basic infrastructure for the management of water *** the increased need for rational water management in Greece,there is not a single network of hydrometeorological *** State Services have established sectional networks of limited coverage,resulting in many *** study aims at the optimisation of the existing network,using GIS *** optimum network of hydrometeorological stations is designed,which constitutes the base for the optimisation of the present *** optimum network consists of 1379 hydrometeorological stations and is based on the guidelines of international *** uniform spatial distribution of the stations and criteria concerning the selection of the appropriate site,such as the low terrain slope,easy accessibility and proximity to special interest points,were of special importance for its ***,only the 20%of the existing stations remain at their locations and are included in the optimised *** rest of the stations should be redistributed according to the proposed sites of the optimum network.

关键词： hydrometeorological network station GIS optimisation

Neoadjuvant therapy for pancreas cancer: Past lessons and future therapies

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World Journal of Gastroenterology 2014年第42期20卷 15564-15579页

作者： Jeffrey m Sutton Daniel e Abbott Department of Surgery Division of Surgical Oncology University of Cincinnati Medical Center

Pancreatic adenocarcinoma remains a most deadly malignancy, with an overall 5-year survival of 5%. A subset of patients will be diagnosed with potentially resectable disease, and while complete surgical resection provides the only chance at cure, data from trials of postoperative chemoradiation and/or chemotherapy demonstrate a modest survival advantage over those patients who undergo resection alone. As such, most practitioners believe that completion of multimodality therapy is the optimal treatment. However, the sequence of surgery, chemotherapy and radiation therapy is frequently debated, as patients may benefit from a neoadjuvant approach by initiating chemotherapy and/or chemoradiation prior to resection. Here we review the rationale for neoadjuvant therapy, which includes a higher rate of completion of multimodality therapy, minimizing the risk of unnecessary surgical resection for patients who develop early metastatic disease, improved surgical outcomes and the potential for longer overall survival. However, there are no prospective, randomized studies of the neoadjuvant approach compared to a surgeryfirst strategy; the established and ongoing investigations of neoadjuvant therapy for pancreatic cancer are discussed in detail. Lastly, as the future of therapeutic regimens is likely to entail patient-specific genetic and molecular analyses, and the treatment that is best applied based on those data, a review of clinically relevant biomarkers in pancreatic cancer is also presented.

关键词： Pancreatic cancer Neoadjuvant therapy Chemotherapy Chemoradiation Biomarkers

Converting TRex-RGB green-channel data to 557.7 nm auroral intensity:methodology and initial results

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earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang D.m.Gillies e.Spanswick e.F.Donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region explorer(TRex)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TRex-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TRex mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TRex spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TRex-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied im.e.iately by TRex-RGB data *** methodology established in this study will also be applicable to the upcoming SmILe ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TRex RGB green-line aurora auroral transport model

Improving electrical,optical and radiation shielding properties of polyvinyl alcohol yttrium oxide composites

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Journal of Rare earths 2023年第12期41卷 2002-2009,I0007页

作者： Shams A.m.Issa D.e.Abulyazied Albandari W.Alrowaily H.A.Saudi e.S.Ali A.m.A.Henaish Hesham m.H.Zakaly Department of Physics Faculty of ScienceUniversity of TabukTabukSaudi Arabia Faculty of Science Al-Azhar UniversityAssiut BranchAssiut71524Egypt Polymer Lab Department of PetrochemicalEgyptian Petroleum Research InstituteNasr CityCairoEgypt Department of Physics College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Physics Department Faculty of ScienceAl-Azhar University(Girls Branch)Nasr CityCairoEgypt Institute of Physics and Technology Ural Federal UniversityYekaterinburg620002Russia Physics Department Faculty of ScienceTanta UniversityTanta31527Egypt Istinye University Faculty of Engineering and Natural SciencesComputer Engineering DepartmentIstanbul34396Turkey

This research aims to study the impact of yttrium oxide on the radiation protection features of polyvinyl alcohol(PVA) for gamma shielding *** yttrium oxide(Y_(2)O_(3)) was instilled through the PVA matrix by different contents(x=0.1 wt%,0,3 wt%,0,7 wt%,0,9 wt%),The morphology of the prepared PVA/Y_(2)O_(3)composites was characterized using scanning electron microscopy(Sem).The samples were investigated using absorption edge,transmittance spectra and dielectric *** transmittance and the bandgap energy decrease as the Y2O3content increases while there is an increase in ε’ and ε" as well as the ac conductivity with the content increment of Y_(2)O_(3)till 0.7 wt%.The te m.e.ature dependence of the dc conductivity was measured for all samples in the range of 260-460 K,and it increases with the tem.e.ature *** correlate the electrical characteristics of the PVA/Y_(2)O_(3)composites with their structure and evaluate electrical properties with the help of equivalent circuit matching with the experimentally electrical response in the im.e.ance spectrum,the radiation protection properties were also investigated to get the radiation shielding performance of these PVA/Y_(2)O_(3)composite films with varying Y_(2)O(3)*** linear attenuation coefficient(μ),half value layer(T_(0.5)),and mass attenuation coefficient(μm) were *** to all obtained data,PVA/Y_(2)O_(3)composite films with various percentages(0.1 wt%,0.3 wt%,0.7 wt%,0.9 wt%) can be used as a radiation shielding material.

关键词： Yttriumoxide/PVA electrical properties Optical properties Gamma shielding Rare earths

Photoluminescence properties of eu3+-doped mgAl2O4 nanoparticles in various surrounding media

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Journal of Rare earths 2019年第8期37卷 806-811,I0001页

作者： I.e.Kolesnikov e.V.Golyeva e.V.Borisov e.Yu Kolesnikov e.Lahderanta A.V.Kurochkin m.D.mikhailov St.Petersburg State University St.PetersburgRussia Lappeenranta University of Technology LUT LappeenrantaFinland Peter the Great St.Petersburg Polytechnic University St.PetersburgRussia Scientific and Technological Institute of Optical material Science VNTs S.I.Vavilov State Optical InstituteSt.PetersburgRussia Volga State University of Technology Yoshkar-OlaRussia

eu3+-doped mgAl2O4 nanoparticles were prepared by modified Pechini method.X-ray diffraction analysis shows pure tetragonal spinel phase without any *** average size of synthesized nanoparticles was determined to be about 50-60 nm using scanning electron microscopy and static light scattering *** and excitation spectra as well as lifetimes of mgAl2O4:eu3+ nanophosphors were explored in surrounding media with different refractive *** medium does not affect luminescence bands position,whereas 5D0 lifetime monotonically decreases along with increase of medium refractive *** of surrounding media on radiative and nonradiative decay rates,which were calculated using 4f-4f intensity theory,was studied and *** factor of prepared nanoparticles is defined using both radiative and observed lifetimes.

关键词： eu3+ Nanoparticles Filling factor Luminescence Lifetime Rare earths

Fuel cell stack design and modelling with a double-stage boost converter coupled to a single-phase inverter

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Clean energy 2024年第1期8卷 188-196页

作者： Basem.e.elnagi Ahmed m.Ismaiel Hany S.e.mansour m.N.Abd-Alwahab electrical engineering Department Faculty of EngineeringSuez Canal UniversityIsmailia 41522Egypt

A comprehensive proton-exchange membrane fuel cell stack model was developed and integrated with a two-stage DC/DC boost *** was directly coupled to a single-phase(two levels-four pulses)inverter without a *** pulse-width modu-lation signal was used to independently regulate every converter *** converter was modelled using a mATLAB®/Simulink®environment and an appropriate voltage control *** analysis features of the suggested circuit were created and,through established experiments,the simulation results were verified.A single-phase(two levels-four pulses)inverter control circuit was tested and it produced a pure sinusoidal waveform with voltage *** matches the voltage of the network in terms of amplitude and frequency.A sinusoidal pulse-width modulation approach was performed using a single-phase(two levels-four pulses)pulse-width modulation *** results demonstrated an enhancement in the standard of the output wave and tuned the dead time with a reduction of 63μs compared with 180μs in conventional techniques.

关键词： Pem fuel cell pulse-width modulation single-phase inverter and double-stage DC/DC boost converter

Noise test of two manufactured power tillers during transport on different local road conditions

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International Journal of Agricultural and Biological engineering 2010年第4期3卷 19-27页

作者： e e Sehsah m A Helmy H m Sorour Department of Agricultural engineering Faculty of Agricultural Kafr El-SheikhKafr El-Sheikh University33516-kafr El-SheikhEgypt

Hearing injury due to exposure to excessive noise during general farming activities is a significant problem for *** present investigation was carried out for better understanding of the noise propagation trends,as well as noise attenuation characteristics of the two different developed power tillers on different surfaces in transportation under egyptian *** egypt,the agricultural roads are one of the main problems that limited the usage of farm *** the last few years,it is noticed that the manufacturers and farmers in egypt applied the diesel engine of command irrigation pump as the source of power for the manufactured power *** their on-farm application in egypt,they are also engaged in transportation of agricultural products and human beings on the asphalt,and dirt rural *** spite of their adverse effects due to noise on operators and bystanders,limited information is available concerning the noise investigation of these manufactured *** aim of this research was to evaluate the noise propagation trends as well as noise attenuation characteristics of the manufactured power tillers on different surfaces in transportation *** developed power tillers that used in this study were fitted with approximately 6 kW(8 hp)and 7.5 kW(10 hp)diesel engines for two different tillers transport *** measurement and recording the sound pressure signals of the power tillers,the variables of engine speeds and gear ratios were varied to cover the most normal range of the power tillers operation in transportation conditions for the asphalt and dirt rural *** test sites were prepared according to SAe noise measurement test *** maximum overall noise measured at driver ear’s position at different gear ratios in asphalt,and dirt rural roads were about 98.2 and 92 dB(A)for 1,350 r/min engine speed which is higher than allowable noise exposure prescribed by National Institute for Occupational Safety a

关键词： noise test power tiller diesel engines transportation manufacture

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涂氏磷钙石:一种磷酸盐高压相新矿物

地球化学 2003年第6期32卷 566-568页

作者：谢先德 m.e. minitti 陈鸣毛河光王德强束今赋费英伟中国科学院广州地球化学研究所广东广州510640 Geophysical Laboratory Carnegie Institution of Washington USA

在随州陨石冲击熔脉中发现了一种磷酸盐新矿物,它是白磷钙石的高压多形,经国际矿物协会新矿物和矿物命名委员会批准,定名为涂氏磷钙石(Tuite)。该矿物属三方晶系,空间群为R-3m,a=5.258(1)?,c=18.727(3)?。一轴晶,正光性,ε=1.706(3),ω=... 详细信息

在随州陨石冲击熔脉中发现了一种磷酸盐新矿物,它是白磷钙石的高压多形,经国际矿物协会新矿物和矿物命名委员会批准,定名为涂氏磷钙石(Tuite)。该矿物属三方晶系,空间群为R-3m,a=5.258(1)?,c=18.727(3)?。一轴晶,正光性,ε=1.706(3),ω=1.701(4)。化学式为(Ca2.51mg0.29)2.80Na0.28(P1.01O4)2,简化式为Ca3(PO4)2。X射线粉晶衍射的强谱线有:2.628(100)、2.891(80)、1.945(47)、1.730(25)和1.567(22)。根据与其共生的其他高压相矿物形成的温压条件和人工合成实验的结果,推定涂氏磷钙石形成的压力为12～23GPa,温度为1400到2000℃。该新矿物以中国矿物岩石地球化学学会的创建人和首任会长涂光炽的姓氏命名。

关键词：涂氏磷钙石白磷钙石磷酸盐新矿物高压多形

effect of Y^(3+), Gd^(3+) and La^(3+) dopant ions on structural, optical and electrical properties of o-mullite nanoparticles

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Journal of Rare earths 2014年第1期32卷 37-42页

作者： m.m.S.Sanad m.m.Rashad e.A.Abdel-Aal m.F.el-Shahat K.Powers Central metallurgical R & D Institute Particle engineering Research Center University of Florida Faculty of Science Ain Shams University

Dielectric ceramics of m（x）Al6（1-x）Si2O13 doped mullite were synthesized via co-precipitation technique. The X-ray diffrac-tion profiles revealed that these nanoparticles were crystallized well and the volume of mullite unit cell was increased as a function of the ionic radius of dopant ion. Tem images showed regular orthorhombic crystal morphology for the pure mullite sample. meanwhile, the doped samples exhibited slightly distorted crystal morphology of larger particle sizes. DSC thermograms evinced that the exo-thermic peak tem.e.ature of mullite was shifted to the lower value with m3＋ion insertion. The photoluminescence spectra were stud-ied for mullite samples, and it was found that the intensity of the emission spectra was affected by the m3＋ion type. It was found that, Y3＋doped mullite achieved the minimum dielectric loss value of 0.01 in the radio wave frequency region （1 mHz）. meanwhile, Gd3＋doped mullite achieved the minimum dielectric loss value of 0.09 in the microwave frequency region （1 GHz）.

关键词： rare earths doped mullite photoluminescence crystallization tem.e.ature dielectric ceramics