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斗轮挖掘机回转支承上部结构中关键部件的静态稳定性基本参数、负载和强度研究（英文）

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第5期17卷 353-365页

作者： Srdan M.bOSNJAK nebojsa b.gnjatovic Sreten D.SAVICEVIC Milorad P.PANTELIC Ivan Lj.MILENOVIC Faculty of Mechanical Engineering University of Belgrade Belgrade 11120 Serbia Faculty of Mechanical Engineering University of Montenegro Podgorica 81000 Montenegro Faculty of Technical Sciences University of Kragujevac Cacak 32000 Serbia

目的：斗轮挖掘机回转支承上部结构的重量和重心位置不仅在设计过程中非常重要,在斗轮挖掘机组装完成后和运转时同样重要。本文旨在研究各参数对重心位置的影响。方法：1.分析比较由数值模拟和实验得到的静态稳定性基本参数;2.构建上部... 详细信息

目的：斗轮挖掘机回转支承上部结构的重量和重心位置不仅在设计过程中非常重要,在斗轮挖掘机组装完成后和运转时同样重要。本文旨在研究各参数对重心位置的影响。方法：1.分析比较由数值模拟和实验得到的静态稳定性基本参数;2.构建上部结构的3D模型（图1-3）,并根据斗轮挖掘机组装完成后的重量分布对模型进行质量修正;3.对上部结构进行负载和应力分析。结论：1.上部结构一个较小的质量变化（1.5%）会导致重心位置一个较大的变化（902 mm）,从而不得不明显增加配重的重量（24 t）来保持平衡;2.构建的3D模型可以得到精确的上部结构重量分布和重心位置;3.由DIN 22261-2标准规定的眼板应力被证明并不安全。

关键词：斗轮挖掘机回转支承上部结构静态稳定性参数负载强度

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Feature Selection Using Grey Wolf Optimization with Random Differential Grouping

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Computer Systems Science & Engineering 2022年第10期43卷 317-332页

作者： R.S.Latha b.Saravana balaji nebojsa bacanin Ivana Strumberger Miodrag Zivkovic Milos Kabiljo Department of Computer Science and Engineering Kongu Engineering CollegeErode638060TamilnaduIndia Department of Information Technology Lebanese French UniversityErbilIraq Singidunum University Belgrade160622Serbia

big data are regarded as a tremendous technology for processing a huge variety of data in a short time and with a large storage *** user’s access over the internet creates massive data processing over the *** data require an intelligent feature selection model by addressing huge varieties of *** feature selection techniques are only applicable to simple data *** techniques are needed in big data processing and machine learning for an efficient *** feature selection algorithms read the input features as they ***,the features are preprocessed and ***,an algorithm does not consider the *** feature selection,all features are misread as ***,a less optimal solution is *** our proposed research,we focus on the feature selection by using supervised learning techniques called grey wolf optimization(GWO)with decomposed random differential grouping(DrnDG-GWO).First,decomposition of features into subsets based on relatedness in variables is *** differential grouping is performed using a fitness value of two ***,every subset is regarded as a population in GWO *** combination of supervised machine learning with swarm intelligence techniques produces best feature optimization results in this *** the features are optimized,we classify using advanced kNN process for accurate data *** result of DrnDGGWO is compared with those of the standard GWO and GWO with PSO for feature selection to compare the efficiency of the proposed *** accuracy and time complexity of the proposed algorithm are 98%and 5 s,which are better than the existing techniques.

关键词： Feature selection data optimization supervised learning swarm intelligence decomposed random differential grouping grey wolf optimization

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Effect of heat treatment on structure and magnetic properties of Fe65.5Cr4Mo4Ga4P12C5b5.5 bulk amorphous alloy

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China Foundry 2017年第1期14卷 59-63页

作者： bratislav Cukic nebojsa Mitrovic Aleksa Maricic Technical College of Vocational Studies 32 000 CacakSerbia Joint Laboratory for Advanced Materials of SASA Section for Amorphous SystemsFaculty of Technical Sciences CacakUniversity of Kragujevae32 000 CacakSerbia

Abstract： This study deals with the Fe65.5Cr4Mo4Ga4P12C5b5.5 ferromagnetic bulk amorphous alloy. XRD analysis showed an amorphous structure of the as-cast sample. The same method revealed that, after annealing at 973 K for v=10 min, the sample displayed a crystalline structure with crystalline phases formed. The crystallization process of the alloy was examined by DTA analysis. It was shown that crystallization took place in the temperature range between 810 K and 860 K with the exo-maximum peak temperature at 846 K with a heating rate of 20 ***-1. The method also showed that, at temperatures ranging from 753 K to 810 K, the alloy exhibited the properties of supercooled liquids. A correlation between heat-induced structural changes and magnetic properties of the alloy was determined by thermomagnetic measurements. Maximum magnetization M=3.7 ***-1 of the alloy was reached after its annealing at 733 K for τ=10 min. Upon annealing, the alloy exhibited a relaxed amorphous structure. Annealing the alloy above the crystallization temperature led to a decrease in bulk magnetization. After annealing at 973 K for r=10 min, the bulk magnetization of the alloy was M＇=0.45 ***-1. Accordingly, after crystallization and formation of new compounds, the magnetization of the alloy was decreased by a factor of about 7.7. The strength of the magnetic field applied during the measurements was H=10 kA.m-1. The samples were tested for changes in the microstructure and hardness of both the amorphous phase and the resulting crystalline phase.

关键词： bulk metallic glass X-ray diffraction analysis differential thermal analysis thermomagneticproperties magnetization hardness microstructure

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Color Doppler sonography and angioscintigraphy in hepatic Hodgkin's lymphoma

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World Journal of Gastroenterology 2009年第26期15卷 3269-3275页

作者： Mirjana V Stojkovi Vera M Artiko Irena b Radoman Slavko J Knezevi Snezana M Luki Mirko D Kerkez nebojsa S Leki Andrija A Anti Marinko M Zuvela Vitomir I Rankovi Milorad N Petrovi Dragana P obi Vladimir b Obradovi Institute for Digestive Diseases Clinical Center of Serbia Institute for Nuclear Medicine Clinical Center of Serbia Gastroenterology Department Clinical Center Podgorica Gastroenterology Department Clinical Center Kragujevac

AIM： To estimate the characteristics of Color Doppler findings and the results of hepatic radionuclide angiography （HRA） in secondary Hodgkin＇s hepatic lymphoma. METHODS： The research included patients with a diagnosis of Hodgkin＇s lymphoma with metastatic focal lesions in the liver and controls. Morphologic characteristics of focal liver lesions and hemodynamic parameters were examined by pulsed and Color Doppler in the portal, hepatic and splenic veins were examined. Hepatic perfusion index （HPI） estimated by HRA was calculated. was observed. Lesions were mostly hypoechoic and mixed, solitary or multiple. Some of the patients presented with dilated splenic veins and hepatofugal blood flow. A pulse wave was registered in the centre and at the margins of lymphoma. The average velocity of the pulse wave was higher at the margins （P 〉 0.05）. A continuous venous wave was found only at the margins of lymphoma. There was no linear correlation between lymphoma size and velocity of pulse and continuous wave （r = 390, P 〈 0.01）. HPI was significantly lower in patients with lymphomas than in controls （P 〈 0.05）, pointing out increased arterial perfusion in comparison to portal perfusion. CONCLUSION： Color Doppler ultrasonography is a sensitive method for the detection of neovascularization in Hodgkin＇s hepatic lymphoma and estimation of its intensity. Hepatic radionuclide angiography can additionally help in the assesment of vascularisation of liver lesions.

关键词： Color Doppler ultrasonography Hodgkin's disease Lymphoma Liver Radionuclide angiography Velocity Hepatic artery Portal vein blood flow Splenomegaly

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Influence of Ni^(2+)/Co^(2+)ratio in electrolyte on morphology,structure and magnetic properties of electrolytically produced Ni-Co alloy powders

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Transactions of Nonferrous Metals Society of China 2020年第4期30卷 1046-1057页

作者： Vesna M.MAKSIMOVIC Vladan b.KUSIGERSKI Milovan M.STOILJKOVIC Jelena R.MALETASKIC nebojsa D.NIKOLIC Institute of Nuclear Sciences “Vinca”University of BelgradeP.O.Box 522Belgrade 11001Serbia Laboratory for Advanced Nuclear Energy Institute of Innovative ResearchTokyo Institute of Technology2-12-1 OokayamaMeguro-kuTokyo 152-8550Japan ICTM-Department of Electrochemistry University of BelgradeNjegoseva 12P.O.Box 473Belgrade 11001Serbia

Nickel-cobalt(Ni-Co) alloy powders were produced galvanostatically by using sulphate electrolytes with various ratios of Ni2+/Co2+(mole ratios). The morphology, phase structure, chemical composition and magnetic properties were examined by scanning electron microscope(SEM), X-ray diffractometer(XRD), atomic emission spectrometer(AES), and SQUID-based magnetometer, respectively. Morphology of the particles changed from cauliflower-like and dendritic to coral-like and spongy-like ones with increasing Ni2+/Co2+ ratio from 0.25 to 4.0. XRD analysis of the Ni-Co powders revealed that the decrease of Ni2+/Co2+ ratios(the increase of Co content) caused a change of structure from face centered cubic(FCC) obtained for the ratios of 4.0, 1.5 and 0.67 to a mixture of FCC and hexagonal closed-packed(HCP) phases for the ratio of 0.25. The increasing content of nickel led to change of mechanism of electrolysis from irregular(up to 40 wt.% Ni in the electrolytes) to close to equilibrium(between 40 and 60 wt.% Ni in the electrolytes) and anomalous co-deposition(over 60 wt.% Ni in the electrolytes) type. All of the obtained Ni-Co alloy samples behaved as soft magnetic materials while their magnetic parameters showed immediate composition dependence since both coercivity and saturation magnetization almost linearly increased with increase of the Co content.

关键词： Ni-Co alloy powders electrolysis hydrogen morphology magnetic properties

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Mn^(5+)-activated Ca_(6)ba(PO_(4))_(4)O near-infrared phosphor and its application in luminescence thermometry

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Light(Science & Applications) 2022年第10期11卷 2463-2475页

作者： Miroslav D.Dramicanin Lkasz Marciniak Sanja Kuzman Wojciech Piotrowski Zoran Ristic Jovana Perisa Ivana Evans Jelena Mitric Vesna Dordevic nebojsa Romcevic Mikhail G.brik Chong-Geng Ma School of Optoelectronic Engineering&CQUPT-bUL Innovation Institute Chongqing University of Posts and TelecommunicationsChongqing 400065PR China Centre of Excellence for Photoconversion Vinca Institute of Nuclear Sciences-National Institute of the Republic of SerbiaUniversity of BelgradeP.O.Box 522Belgrade 11001Serbia Institute of Low Temperature and Structure Research Polish Academy of SciencesOkólna 250-422 WroclawPoland Department of Chemistry Durham UniversityDurham DH13LEUK Institute of Physics University of BelgradePregrevica 11811080 BelgradeSerbia Institute of Physics University of TartuTartu 50411Estonia Department of Theoretical Physics Jan D?ugosz UniversityCzestochowa PL 42200Poland Academy of Romanian Scientists Ilfov Str.No.3050044 BucharestRomania

The near-infrared luminescence of Ca_(6)ba(PO_(4))_(4)O∶Mn^(5+)is demonstrated and *** excited into the broad and strong absorption band that spans the 500-1000 nm spectral range,this phosphor provides an ultranarrow(FWHM=5 nm)emission centered at 1140 nm that originates from a spin-forbidden ^(1)E → ^(3)A_(2) transition with a 37.5%internal quantum efficiency and an excited-state lifetime of about 350 μ*** derived the crystal field and Racah parameters and calculated the appropriate Tanabe-Sugano diagram for this *** found that 1E emission quenches due to the thermally-assisted cross-over with the ^(3)T_(2) state and that the relatively high Debye temperature of 783 K of Ca_(6)ba(PO_(4))_(4)O facilitates efficient *** Ca_(6)ba(PO_(4))_(4)O also provides efficient yellow emission of the Eu^(2+)dopant,we calculated and explained its electronic band structure,the partial and total density of states,effective Mulliken charges of all ions,elastic constants,Debye temperature,and vibrational ***,we demonstrated the application of phosphor in a luminescence intensity ratio thermometry and obtained a relative sensitivity of 1.92%K^(-1) and a temperature resolution of 0.2 K in the range of physiological temperatures.

关键词： spectra. luminescence excited

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