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步行路径推荐服务开发

步行路径推荐服务开发

作者： semenov alexander 武汉大学

学位级别：硕士

时至今日,人们使用智能手机上所推荐的最短路径服务,有时候并不是我们真正所需要的.其实只有我们驾驶汽车的时候,智能手机上所提供的最短路径才是我们需要的.但在步行的时候,我们会更多的考虑周围的环境(比如噪声/空气质量/环境是否优... 详细信息

时至今日,人们使用智能手机上所推荐的最短路径服务,有时候并不是我们真正所需要的.其实只有我们驾驶汽车的时候,智能手机上所提供的最短路径才是我们需要的.但在步行的时候,我们会更多的考虑周围的环境(比如噪声/空气质量/环境是否优美以及是否安全等)来决定选择哪条路线步行.在大多数情况下,我们想要穿过恬静优雅的地方,那里绿意盎然,环境优美,阳光明媚.然而,目前的研究只考虑了部分相关的环境因素,并没有把这些因素统一放到一个模型里面统一研究.本文以圣彼得堡为例,通过综合考虑各种环境因素,构架了一个统一的模型,并依据该模型开发了一个简单的导航服务.我设计了一个调查问卷,用来调查一个地方对喜欢步行的人的吸引力.该问卷获得了来自不同年龄和性别的58个人的反馈,所有这些反馈形成了一个城市不同地区的五星评分样本。我基于获得的样本,利用随机森林算法,创建了位置吸引力模型,该模型通过考虑一个地方的喧闹程度,建筑风格,来自社交媒体的照片,离水域的距离,绿化程度,是否是工业区域来度量一个地方所处位置的吸引力程度(很好,一般,不好).模型在实验数据集上,总体上的f1分数约为0.6,好的和坏的f1分数分别为0.83和0.65,取得了较好的效果.基于该模型,我对圣彼得堡所有的人行通道的吸引力程度进行了评估.为了创建导航服务,我们比较了两种路径优化方法:一种是基于经典的Dijkstra最短路径算法,将路径的权重设置为吸引力模型所得到的位置吸引力程度,另一种则使用Yen的k-最短路径算法,在找到的前N个最短路径中寻找位置吸引力均值最大的.通过比较,我发现Dijkstra最短路径算法优于Yen的k-最短路径算法,并且使用加权Dijkstra最短路径算法所得到的最短路径和实际的最短路径长度基本相同(长6%).最后,基于加权的Dijkstra最短路径算法,我设计并开发了导航的原型系统.该系统给出算法推荐的几条步行路径,并给出相关的结果比如路径吸引力程度以及路径步行时间,以便用户进行比较选择.人工分析表明,在城市的各个地方,该系统都能够有效的推荐出相关的路径。

关键词：行人导航步行路线随机森林应用设计

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极地冰层下的生命

人与自然 2012年第5期 46-55页

作者：孙松 alexander semenov

北极冰层下的精灵北极地区茫茫冰盖，看上去辽远而宁静……白海位于俄罗斯欧洲部分的北部。那里的冬天来得特别早，10月的气温就降到0cc以下，并且开始下雪。到了12月，除了有强劲洋流的地方，整个白海几乎完全被冰所覆盖，一直到次年4... 详细信息

北极冰层下的精灵北极地区茫茫冰盖，看上去辽远而宁静……白海位于俄罗斯欧洲部分的北部。那里的冬天来得特别早，10月的气温就降到0cc以下，并且开始下雪。到了12月，除了有强劲洋流的地方，整个白海几乎完全被冰所覆盖，一直到次年4月或5月。

关键词：北极地区冰层生命俄罗斯白海冰盖气温洋流

Peculiarities of Ethylene Polymerization Reactions with Bis(imino)pyridyl Complexes of CoCl_(2) and FeCl_(2)

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Chinese Journal of Polymer Science 2024年第4期42卷 492-500页

作者： Laura A.Rishina Yury V.Kissin Svetlana S.Lalayan Artem A.Antonov Vadim G.Krasheninnikov alexander A.Gulin N.N.semenov Federal Research Center for Chemical Physics Russian Academy of Sciences4 Kosygin St.Moscow119991Russia Department of Chemistry and Chemical Biology RutgersThe State University of New Jersey123 Bevier Rd.PiscatawayNJ08854USA Boreskov Institute of Catalysis Russian Academy of Sciences5 Lavrentieva Prosp.Novosibirsk630090Russia

The article describes ethylene polymerization reactions with transition metal catalysts based on complexes of CoCl_(2) and FeCl_(2) with an N,N,N-tridentate ligand 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine. The complexes are converted into polymerization catalysts by reacting them either with polymethylalumoxane (MAO) or with a combination of Al(C2H5)2Cl and Mg(C4H9)2 at an [Al]:[Mg] ratio of ~3. Both MAO-activated complexes readily polymerize ethylene at 35 ℃ with the formation of linear, low molecular weight polymers with a narrow molecular weight distribution. The same complexes, when activated with the Al(C2H5)2Cl-Mg(C4H9)2 combination, form multi-center catalysts and generate polyethylenes with a broad molecular weight distribution.

关键词： Ethylene polymerization Bis(imino)pyridyl complexes of CoCl_(2)and FeCl_(2) Molecular-weight distribution Polymer chain structure

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海洋“生物猎人”的发现之旅

人与自然 2014年第6期 62-85页

作者：保尔·罗斯张帆商睿王嘉华林青潘迎久杜锦恩 alexander semenov

在大多数人眼里，平坦的海洋也许平淡无奇。然而，看似平静的表面下隐藏的却是一个截然不同的世界，各种神奇而又罕见的生物栖息其中。地球上4/5的生物都生活在海洋里，有数百万的新物种有待我们去发现。绝大部分的海底生物都具有药用... 详细信息

在大多数人眼里，平坦的海洋也许平淡无奇。然而，看似平静的表面下隐藏的却是一个截然不同的世界，各种神奇而又罕见的生物栖息其中。地球上4/5的生物都生活在海洋里，有数百万的新物种有待我们去发现。绝大部分的海底生物都具有药用价值，海洋就是一个无边无际的百草园。有那么一群人活跃在海里，寻觅、搜集、分类、研究……他们是当代海底“神农”。

关键词：海底生物海洋猎人药用价值新物种栖息

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大洋下的生命伊甸园

人与自然 2014年第6期 10-43页

作者：李春梅张帆杜锦恩 alexander semenov 商睿王嘉华林青谢墨坤坤

蓝色是我们这个星球的基调，从外层太空拍摄到的照片看起来，地球大部分都是蓝色的。地球表面约有百分之七十被海洋覆盖着，照片中所呈现的蓝色就是海水。生命源于这片蓝色，最终也将归于这片蓝色。

关键词：生命源大洋地球表面太空拍摄蓝色照片海洋海水

Forces of RBC interaction with single endothelial cells in stationary conditions:Measurements with laser tweezers

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Journal of Innovative Optical Health Sciences 2021年第5期4卷 53-63页

作者： Arseniy A.Kapkov Alexey N.semenov Petr B.Ermolinskiy Andrei E.Lugovtsov alexander V.Priezzhev Faculty of Physics Lomonosov Moscow State UniversityLeninskie GoryMoscow 119991Russia Faculty of Biology Lomonosov Moscow State UniversityLeninskie GoryMoscow 119991Russia

Red blood cells(RBCs)are able to interact and communicate with endothelial cells(ECs).Under some pathological or even normal conditions,the adhesion of RBCs to the endothelium can be ***,the mechanisms and many aspects of the interaction between RBCs and ECs are not fully *** this work,we considered the interaction of single RBCs with single ECs in vitro aiming to quantitatively determine the force of this interaction using laser *** were performed under different concentrations of proaggregant macromolecules and in the presence or absence of tumor necrosis factor(TNF-α)activating the *** have shown that the strength of interaction depends on the concentration of fibrinogen or dextran proaggregant macromolecules in the environment.A nonlinear increase in the force of cells interaction(from 0.4 pN to 21 pN)was observed along with an increase in the fibrinogen con-centration(from 3 mg/mL to 9 mg/mL)in blood plasma,as well as with the addition of dextran macromolecules(from 10 mg/mL to 60 mg/mL).Dextran with a higher molecular mass(500 kDa)enhances the adhesion of RBCs to ECs greater compared to the dextran with a lower molecular mass(70 kDa).With the preliminary activation of ECs with TNF-α,the force of interaction ***,the adhesion of echinocytes to EC compared to discocytes is significantly *** results may help to better understand the process of interaction between RBCs and ECs.

关键词： Endothelial cells red blood cells laser tweezers adhesion

Blocking Anticyclone in the Atlantic Sector of the Arctic as an Example of an Individual Atmospheric Vortex

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Atmospheric and Climate Sciences 2017年第3期7卷 323-336页

作者： alexander Kislov Natalia Sokolikhina Eugene semenov Kirill Tudriy Department of Meteorology and Climatology Lomonosov Moscow State University Moscow Russia

The task of vortex boundaries setting is one of the most complexes in examination of factors influencing on the vortex (circulation system) development and destruction. In this study a new approach of vortex analysis as a whole system is proposed. It is based on vorticity equation where vorticity (left part of the equation) is defined as time coefficients of EOF-decomposition, which is integrated indexes characterizing individual vortex dynamics. Right part of the vorticity equation depicts internal and external factors influencing on the vortex. It's approbation is done on the example of an arctic-subarctic circulation system including blocking anticyclone in winter 2012 which persisted for a long time over the Atlantic sector of the Arctic and led to the formation of the largest positive air temperature anomalies and the minimum ice cover area in the Barents and Kara seas in the entire history of regular observations. It is shown that the main factor in long-term maintenance of the blocking anticyclone over the Arctic was vorticity advection, which was stabilized by horizontal heat advection.

关键词： Blocking Anticyclone Arctic Warming an Individual Atmospheric Vortex

Facile Synthesis of Amino Acid Decorated Water-Soluble Fullerene Derivatives with Anti-influenza Activity

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Chinese Journal of Chemistry 2023年第15期41卷 1803-1808页

作者： Valeriya S.Bolshakova Ekaterina O.Sinegubova Yana L.Esaulkova alexander S.Peregudov Ekaterina A.Khakina Nikita A.Slesarenko alexander F.Shestakov Vladimir V.Zarubaev Pavel A.Troshin Olga A.Kraevaya Federal Research Center for Problems of Chemical Physics and Medicinal Chemistry of RAS Academician Semenov ave.1Chernogolovka142432Russia Higher Chemical College of RAS D.1.Mendeleev University of Chemical Technology of RussiaMiusskaya square 9Moscow125047Russia St.Petersburg Pasteur Institute Mira st.14St.Petersburg197101Russia A.N.Nesmeyanov Institute of Organoelement compounds of RAS Vavylova St.28B-334Moscow119991Russia National Research University Higher School of Economics Vavylova St.7Moscow101000Russia Department of Fundamental Physics&Chemical Engineering M.V.Lomonosov Moscow State UniversityLeninskie Gory 1/51Moscow119991Russia Zhengzhou Research Institute Harbin Institute of TechnologyLongyuan East 7th 26Jinshui DistrictZhengzhouHenan 450003China Harbin Institute of Technology West Dazhi Street 92Nan Gang DistrictHarbinHeilongjiang 150001China

Comprehensive Summary Herein,we present a facile synthesis of amide-type water-soluble fullerene derivatives decorated with five residues of amino *** compared to the previously developed approaches,the proposed method enables usage of a broad range of amino acids,including those unstable under Friedel-Crafts reaction ***,it is fully tolerant to the nature of the sixth addend X in C60R5X precursor compounds and allows one to obtain fullerene derivatives with X=Cl,H,*** synthesized amide-type water-soluble fullerene derivatives demonstrated promising antiviral activities against rimantadine-resistant influenzaА/Puerto Rico/8/34(Н1N1)virus in vitro.

关键词： Fullerenes Amino acids Regioselectivity Water-solublel Influenza Antiviral

Ignition of nanothermites by a laser diode pulse

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Defence Technology（防务技术） 2022年第2期18卷 194-204页

作者： alexander Yu.Dolgoborodov Vladimir G.Kirilenko Michael A.Brazhnikov Leonid I.Grishin Michael L.Kuskov Georgii E.Valyano Joint Institute for High Temperatures Russian Academy of SciencesRussia N.semenov Federal Research Center for Chemical Physics Russian Academy of SciencesRussia National Research Nuclear University MEPhI Moscow Russia

Experimental investigation has been carried out for laser ignition and combustion of nanothermites based on aluminum and oxides of copper,bismuth and *** mixing of nanosized powders was used to produce *** thermite ignition,initiating laser pulse with a maximum intensity of 770 W/cm2 was generated by a laser diode with a wavelength of 808 *** ignition delay times,the minimum initiation energy density,and the average burning rate at various thermite densities and mass fractions of components were determined by recording the emission of radiation of the reaction products using a multichannel pyrometer jointly with a high-speed video *** effect of adding carbon black on the threshold parameters of a laser pulse was also *** on the obtained results,certain assumptions were put forward with regard to the mechanism of nanothermites’ignition by laser radiation and their *** particular,the assumptions were made on the two-stage process of the reaction initiation and jet burning mechanism of porous nanothermites.

关键词： Nanothermites Laser ignition Burning rate Ignition delay