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Search for giant pulses of radio pulsars at frequency 111 MHz with LpA radio telescope

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Research in Astronomy and Astrophysics 2018年第8期18卷 71-82页

作者： Andrey Nikolaevich Kazantsev Vladimir Alexeevich potapov E N.Lebedev physical Institute of the Russian Academy of Sciences Pushchino Radio Astronomy ObservatoryPushchino 142290Russia

We have used the unique low frequency sensitivity of the Large phased Array （LpA） radio telescope of pushchino Radio Astronomy Observatory to collect a dataset consisting of single pulse observations of second period pulsars in the Northern Hemisphere. During observation sessions in 2011- 2017, we collected data on 71 pulsars at a frequency of 111 MHz using a digital pulsar receiver. We have discovered Giant Radio pulses （GRps） from pulsars B0301＋09 and B 1237＋25, and confirmed earlier reported generation of anomalously strong （probable giant） pulses from B 1133＋16 in a statistically significant dataset. Data for these pulsars and from B0950＋08 and B 1112＋50, earlier reported as pulsars generating GRps, were analyzed to evaluate their behavior over long time intervals. It was found that the statistical criterion （power-law spectrum of GRp distribution of energy and peak flux density） seems not to be strict for pulsars with a low magnetic field at their light cylinder. Moreover, spectra of some of these pulsars demonstrate unstable behavior with time and have a complex multicomponent shape. In the dataset for B0950＋08, we have detected the strongest GRp from a pulsar with a low magnetic field at its light cylinder ever reported, having a peak flux density as strong as 16.8 kJy.

关键词： stars neutron - pulsars general - pulsars individual (pSR B0301+19 pSR B0320+39 pSR B0329+54 pSR B0809+74 pSR B0950+08 pSR B1112+50 pSR B1133+16 pSR B1237+25) - pulsars giant pulses individual pulses

A review of dielectric optical metasurfaces for spatial differentiation and edge detection

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Frontiers of Optoelectronics 2021年第2期14卷 187-200页

作者： Lei WAN Danping pAN Tianhua FENG Weiping LIU Alexander A.potapov Department of Electronic Engineering College of Information Science and TechnologyJinan UniversityGuangzhou 510632China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China JNU-IREE RAS Joint Laboratory of Information Techniques and Fractal Signal processing Jinan UniversityGuangzhou 510632China Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Education Institutes Jinan UniversityGuangzhou 510632China Institute of Radio Engineering and Electronics Russian Academy of SciencesMoscow 125009Russia

Dielectric metasurfaces-based planar optical spatial differentiator and edge detection have recently been proposed to play an important role in the parallel and fast image processing *** the development of dielectric metasurfaces of different geometries and resonance mechanisms,diverse on-chip spatial differentiators have been proposed by tailoring the dispersion characteristics of subwavelength *** review focuses on the basic principles and characteristic parameters of dielectric metasurfaces as first-and second-order spatial differentiators realized via the Green's function *** spatial bandwidth and polarization dependence are emphasized as key properties by comparing the optical transfer flinctions of metasurfaces for different incident wavevectors and *** present the operational capabilities of a two-dimensional spatial differentiator in image information acquisition,edge detection is described to illustrate the practicability of the *** an application example,experimental demonstrations of edge detection for different biological cells and a flower mold are discussed,in which a spatial differentiator and objective lens or camera are integrated in three optical pathway *** realization of spatial differentiators and edge detection with dielectric metasurfaces provides new opportunities for ultrafast information identification in biological imaging and machine vision.

关键词： dielectric metasurfaces spatial differentiator edge detection optical transfer function

Effects of Slight plastic Deformation on Magnetic properties and Giant Magnetoimpedance of FeCoCrSiB Amorphous Ribbons

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Chinese physics Letters 2007年第5期24卷 1357-1360页

作者： S. O. Volchkov M. A. Cerdeira V. V. Gubernatorov E. I. Duhan A. p. potapov V. A. Lukshina Ural State University Lenin Ave. 51 Yekaterinburg 620083 Russia Dpto. de Ffsica Universidad 'de Oviedo Avd. Calvo Sotelos/n 33007 Oviedo Spain Institute of Metal physics Ural Branch of RAS Yekaterinburg 620041 Russia

Slight plastic deformation of 0 to 1% by cold rolling is proposed as a treatment which may modify the responses of magnetoimpedance （MI） sensor with an amorphous ribbon used as a sensitive element. The dependence of the magnetic properties of melt spun Fe3Co67Cr3Si15B12 amorphous ribbons and their MI responses in the initial state and after slight plastic deformation on the value of the deformation were comparatively analysed. The shape of the hysteresis loops shows a clear correlation with the value of the deformation. The variations of the total impedance, the real and the imaginary components, are measured for the current intensity of 1.S mA for the frequency of lO MHz. Slight plastic deformation affects both real and imaginary components and allows a control of the shape of the MI curves in a small field in a range usually used in biomedical applications. The proposed deformation treatments can be useful for the construction of the MI sensitive elements with a new type of the responses.

关键词： IMpEDANCE SENSOR

Variations of the Magnetosphere Resonance Frequencies During Magnetic Storm of July 15-16,2000

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空间科学学报 2005年第5期25卷 387-392页

作者： A. potapov A. polyakov T. polyushkina H. Zhao Institute of Solar-Terrestrial physics Siberia Branch Russian Academy of Sciences Irkutsk 664033 Russia National Microwave Remote Sensing Laboratory Center for Space Science and Applied Research Chinese Academy of Sciences

ULF observations at two mid-latitude sites during the large geomagnetic storm of July 15-16,2000 were used to trace variations of resonance frequencies of the field line resonators. A brief description of the geomagnetic disturbance as it was observed on the ground, at the geostationary orbit, and before the Earth's bow shock is given. Then a detailed study of ULF dynamic spectra from Borok and Mondy is performed for8 succesive 6-hour intervals of July 15 and 16. In conclusion some tasks for the future work are listed.

关键词：等离子体磁场磁气圈空间气候

Clipping versus coiling in posterior circulation intracranial aneurysms: a meta-analysis

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Chinese Neurosurgical Journal 2019年第3期5卷 151-162页

作者： Eleni Tsianaka Abdullah Al-Shawish Alexander potapov Kostas Fountas Michael Spyrou Nikolay Konovalov Department of Neurosurgery University Hospital of LarissaViopolis41111LarissaGreece Department of Neurosurgery Ibn Sina HospitalSabahMedical AreaShuwaikhKuwait Department of Neurotraumatology “N.N.Burdenko”Neurosurgery Institute164th Tverskaya–Yamskaya Str.MoscowRussia Department of Neurosurgery Ygeia Private HospitalGolgon333025LimassolCyprus Department of Spine Neurosurgery “N.N.Burdenko”Neurosurgery Institute164th Tverskaya–Yamskaya Str.MoscowRussia.

posterior circulation intracranial aneurysm (IA) treatment remains challenging, due to the anatomy of the area and the high rupture possibility. Endovascular treatment seems to be more suitable for these aneurysms, but studies focused on endovascular treatment demonstrate a high rate of re-intervention needing. A meta-analysis might offer a clearer view, being useful in a more effective treatment planning. Methods: A systematic search was performed, using the pubMed database platform. The final article pool contained 20 articles. Studied parameters were operative mortality, late mortality, permanent neurologic deficit (pND), and the need for re-intervention (Re-int). We divided patients into two subgroups, those with ruptured and those with unruptured aneurysm. Statistical analysis was performed using appropriate software. Results: In the total population (645 patients), there was a superiority of coiling over clipping in terms of pND and of coiling in terms of Re-int. As regards mortality, there was no clear superiority of one method over the other. Conclusions: The current study came to the conclusion that there is a superiority of coiling over clipping in terms of pND. On the other hand, clipping seems to be superior to coiling in terms of the need for re-intervention. As regards mortality (both operative and late), there is no clear superiority of one method over the other. Studying subgroups of patients (ruptured and unruptured posterior circulation IAs), in terms of pND, there is no superiority of one method over the other. The same goes for Op-Mo on ruptured aneurysms.

关键词： Clipping Coiling Intracranial aneurysms Meta-analysis posterior circulation

Laplace metasurfaces for optical analog computing based on quasi-bound states in the continuum

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photonics Research 2021年第9期9卷 1758-1766页

作者： DANpING pAN LEI WAN MIN OUYANG WEI ZHANG ALEXANDER A.potapov WEIpING LIU ZIXIAN LIANG TIANHUA FENG ZHAOHUI LI Department of Electronic Engineering College of Information Science and TechnologyJinan UniversityGuangzhou 510632China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060China State Key Laboratory of Optoelectronic Materials and Technologies and School of Electronics and Information Technology Sun Yat-sen UniversityGuangzhou 511400China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China

Laplace operation,the isotropic second-order differentiation,on spatial functions is an essential mathematical calculation in most physical equations and signal *** the Laplace operation in a manner of optical analog computing has recently attracted attention,but a compact device with a high spatial resolution is still ***,we introduce a Laplace metasurface that can perform the Laplace operation for incident lightfield *** exciting the quasi-bound state in the continuum,an optical transfer function for nearly perfect isotropic second-order differentiation has been obtained with a spatial resolution of wavelength *** a Laplace metasurface has been numerically validated with both 1D and 2D spatial functions,and the results agree well with that of the ideal Laplace *** addition,the edge detection of a concerned object in an image has been demonstrated with the Laplace *** results pave the way to the applications of metasurfaces in optical analog computing and image processing.

关键词： surface quasi continuum

Mapping wetlands in Indonesia using Landsat and pALSAR data-sets and derived topographical indices

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Geo-Spatial Information Science 2014年第1期17卷 60-71页

作者： Belinda A.MARGONO Jean-Robert B.BWANGOY peter V.potapov Matthew C.HANSEN Department of Geographical Sciences University of Maryland4321 Hartwick Bld.College ParkMD 20742USA GIS Center of Excellence South Dakota State University1021 Medary Ave.Wecota HallBrookingsSD 57007USA The Ministry of Forestry(MoF)of Indonesia Manggala Wanabhkati Bld.Jakarta 10270Indonesia

Wetlands play an important role in the provision of ecosystem services,ranging from the regulation of hydrological systems to carbon sequestration and biodiversity *** paper reports the mapping of Indonesia’s wetland cover as a single thematic class,including peatlands,freshwater wetlands,and ***-interpreted training data were used to identify wetland formations including areas of likely past wetland extent that have been converted to other land *** indices(Shuttle Radar Topography Mission-derived)and optical(Landsat)and radar(pALSAR)image inputs were used to build a bagged classification tree model based on training data in order to generate a national-scale map of wetland extent at a 60 m spatial *** resulting wetland map covers 21.0%(39.6 Mha)of Indonesia’s land,including 25.2% of Sumatra(11.9 Mha),22.9% of Kalimantan(12.2 Mha),and 28.9% of papua(11.8 Mha).Results agree with existing image-interpreted products from Indonesia’s Ministries of Forestry and Agriculture and Wetlands International(89% overall agreement),and with the Ministry of Forestry forest inventory data for Sumatra and Kalimantan(91% overall agreement).An internally consistent algorithm-derived national wetland extent map can be used to quantify changing rates of land conversion inside and outside of ***,wetlands extent can be used to efficiently allocate field resources in national assessments of wetland sub-types such as peatlands,which are a current focus of policies aiming to reduce carbon emissions from land use change.

关键词： wetlands Indonesia remote sensing Landsat digital elevation model(DEM) pALSAR Shuttle Radar Topography Mission(SRTM)

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鸟类对欧亚地区高山生活的适应(英文)

动物学报 2004年第6期50卷 970-977页

作者： Roald L. potapov Zoological Institute Russian Academy of Sciences St. Petersburg Russia

欧亚地区高地鸟类区系的贫乏性 (仅有 75种繁殖于林线之上 )受严酷的自然条件和食物资源短缺所决定。适合这些条件的主要适应是飞行模式 ,包括与之有关的形态特征 ,繁殖时间的选择 ,最优化利用微生境和伪装的巢址选择 ,窝卵数的限制 ,... 详细信息

欧亚地区高地鸟类区系的贫乏性 (仅有 75种繁殖于林线之上 )受严酷的自然条件和食物资源短缺所决定。适合这些条件的主要适应是飞行模式 ,包括与之有关的形态特征 ,繁殖时间的选择 ,最优化利用微生境和伪装的巢址选择 ,窝卵数的限制 ,对雏鸟的食物转运模式 ,防护强紫外线辐射和大气干燥。

关键词：鸟类区系巢址选择窝卵数微生境雏鸟生活史特征动物学繁殖时间高山形态特征

Exact Quasi-Classical Asymptotic beyond Maslov Canonical Operator and Quantum Jumps Nature

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Journal of Applied Mathematics and physics 2015年第5期3卷 584-607页

作者： Jaykov Foukzon Alex potapov Stanislav podosenov Israel Institute of Technology Haifa Israel The Institute of Radioengineering and Electronics (IRE) of Russian Academy of Sciences Moscow Russian All-Russian Scientific-Research Institute Moscow Russian

Exact quasi-classical asymptotic beyond WKB-theory and beyond Maslov canonical operator to the Colombeau solutions of the n-dimensional Schrodinger equation is presented. Quantum jumps nature is considered successfully. We pointed out that an explanation of quantum jumps can be found to result from Colombeau solutions of the Schrodinger equation alone without additional postulates.

关键词： Quantum Jumps Quantum Measurements Theory Quantum Averages Limiting Quantum Trajectory Schrodinger Equation Stochastic Quantum Jump Equation Colombeau Solution Feynman path Integral Maslov Canonical Operator Feynman-Colombeau propagator