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Defence Technology（防务技术） 2017年第3期13卷 177-187页

作者： vladimir Cech Jiri Jevicky Department of Weapons and Ammunition University of Defence Oprox Inc. Department of Mathematics and Physics University of Defence

Projectile trajectories calculated under non-standard conditions are considered to be perturbed. The tools utilized for the analysis of perturbed trajectories are weighting factor functions(WFFs) which are a special kind of sensitivity functions. WFFs are used for calculation of meteo ballistic elements mB(ballistic wind wB, virtual temperature tB, pressure pB, density rB, speed of sound a) as well. An effect of weapon system parameters can be incorporated into calculations through the reference height of *** are also calculated from WFFs. Methods based on RHT are far more effective than traditional methods that use weighting factors *** have found that the existing theory of RHT has several shortcomings due to we created an improved theory of generalized RHT which represent a special sensitivity parameters of dynamical systems. Using this theory will improve methods for designing firing tables, fire control systems algorithms, and meteo message generation algorithms.

关键词：灵敏度函数气象要素弹道风特征动力系统理论消防控制系统加权因子生成算法

‘Relationships between relationships’ in forest stands: intercepts and exponents analyses

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Journal of Forestry Research 2018年第3期29卷 575-582页

作者： vladimir L.Gavrikov institute for Ecology and Geography Chair of Ecology and Environmental Studies Siberian Federal University

Relationships between diameter at breast height(dbh) versus stand density, and tree height versus dbh(height curve) were explored with the aim to find if there were functional links between correspondent parameters of the relationships, exponents and intercepts of their power functions. A geometric model of a forest stand using a conic approximation suggested that there should be interrelations between correspondent exponents and intercepts of the relationships. it is equivalent to a type of ‘relationship between relationships’ that might exist in a forest stand undergoing self-thinning, and means that parameters of one relationship may be predicted from parameters of another. The predictions of the model were tested with data on forest stand structure from published databases that involved a number of trees species and site quality levels. it was found that the correspondent exponents and intercepts may be directly recalculated from one another for the simplest case when the total stem surface area was independent of stand density. For cases where total stem surface area changes with the drop of density, it is possible to develop a generalization of the model in which the interrelationships between correspondent parameters(exponents and intercepts) may be still established.

关键词： Total stem surface area Self-thinning Conic approximation Power function Exponent intercept Scots pine

improved theory of generalized meteo-ballistic weighting factor functions and their use

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Defence Technology（防务技术） 2016年第3期12卷 242-254页

作者： vladimir CECH Jiri JEViCKY Department of Weapons and Ammunition University of Defence Oprox Inc. Department of Mathematics and Physics University of Defence

it follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire error budget *** calculated under non-standard conditions are considered to be *** tools utilized for the analysis of perturbed trajectories are weighting factor functions(WFFs)which are a special kind of sensitivity *** are used for calculation of meteo ballistic elements B(ballistic wind w B,densityρB,virtual temperatureτB,pressure p B)as *** have found that the existing theory of WFF calculation has several significant *** aim of the article is to present a new,improved theory of generalized WFFs that eliminates the deficiencies *** this theory will improve methods for designing firing tables,fire control systems algorithms,and meteo message generation algorithms.

关键词： Exterior ballistic Non-standard projectile trajectory Perturbation Meteoconditions Sensitivity function (Generalized) weighting (factor) function(curve) (Generalized) effect function Norm effect

Ten years of spasers and plasmonic nanolasers

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Light(Science & Applications) 2020年第1期9卷 1133-1153页

作者： Shaimaa i.Azzam Alexander V.Kildishev Ren-Min Ma Cun-Zheng Ning Rupert Oulton vladimir M.Shalaev Mark i.Stockman Jia-Lu Xu Xiang Zhang School of Electrical&Computer Engineering and Birck Nanotechnology Center Purdue UniversityWest LafayetteIN 47907USA Purdue Quantum Science and Engineering institute Purdue UniversityWest LafayetteIN 47907USA State Key Lab for Mesoscopic Physics and School of Physics Peking UniversityBeijingChina Frontiers Science Center for Nano-optoelectronics&Collaborative innovation Center of Quantum Matter BeijingChina Department of Electronic Engineering and international Center for Nano-Optoelectronics Tsinghua University100084 BeijingChina School of Electrical Computerand Energy EngineeringArizona State UniversityTempeAZ 85287USA The Blackett Laboratory Imperial College LondonSouth KensingtonLondon SW72AZUK Center for Nano-Optics(CeNO)and Department of Physics and Astronomy Georgia State UniversityAtlantaGA 30303USA Nanoscale Science and Engineering Center University of CaliforniaBerkeleyBerkeleyCA 94720USA Faculties of Sciences and Engineering University of Hong KongHong KongChina

Ten years ago,three teams experimentally demonstrated the first spasers,or plasmonic nanolasers,after the spaser concept was first proposed theoretically in *** overview of the significant progress achieved over the last 10 years is presented here,together with the original context of and motivations for this *** a general introduction,we first summarize the fundamental properties of spasers and discuss the major motivations that led to the first demonstrations of spasers and *** is followed by an overview of crucial technological progress,including lasing threshold reduction,dynamic modulation,room-temperature operation,electrical injection,the control and improvement of spasers,the array operation of spasers,and selected applications of single-particle *** prospects are presented in relation to several directions of development,including further miniaturization,the relationship with Bose-Einstein condensation,novel spaser-based interconnects,and other features of spasers and plasmonic lasers that have yet to be realized or challenges that are still to be overcome.

关键词： lasers overcome operation

Rationally connected varieties -On a conjecture of Mumford

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Science China Mathematics 2017年第6期60卷 1019-1028页

作者： LAZiC vladimir PETERNELL Thomas Mathematisches institut Universitat Bonn Bonn 53115 Germany Mathematisches institut Universitat Bayreuth Bayreuth 95440 Germany

We establish a conjecture of Mumford characterizing rationally connected complex projective manifolds in several cases.

关键词： rationally connected varieties Mumford conjecture non vanishing conjecture abundance

Ecology and social behavior of the social vole Microtus socialis: A generalized review

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Current Zoology 2023年第6期69卷 775-783页

作者： vladimir S.Gromov A.N.Severtsov institute of Ecology and Evolution Leninsky prosp.33Moscow 119071Russia

The present review is a compilation of the published data on the ecology and social behavior of the social *** studies provide evidence that these voles live in family groups consisting of 1 adult male,1 or 2 breeding females,and their offspring(1 or 2 litters).The social vole is capable of year-round reproduction,but in arid regions,the voles demonstrate seasonality in *** mating system of this species may be defined as behavioral monogamy.A typical feature of the space use system is territoriality characterized by a locus-dependent dominance in relationships between neighboring breeding pairs as well as family *** family group social organization may be defined as consistent relationships without a dominant *** voles are cooperative in defending their territories,constructing burrows,digging underground tunnels,maintaining nests,and raising *** appears to enhance the survival of family groups of this species under the extreme climaticconditionsof Central Asia.

关键词： ecology family-group lifestyle mating system reproduction social organization social vole

Fragmentation model for large L/D (Length over Diameter) explosive fragmentation warheads

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Defence Technology（防务技术） 2017年第4期13卷 300-309页

作者： vladimir M. Gold US Army RDECOM-ARDEC Attn: RDAR-MEE-F Picatinny Arsenal NJ 07806-5000 USA

New advanced numerical computer model enabling accurate simulation of fragmentation parameters of large Length over Diameter(L/D)explosively driven metal shells has been developed and *** newly developed large L/D multi-region model links three-dimensional axisymmetric high strain high strain-rate hydrocode analyses with the conventional set of Picatinny Arsenal FRAGmentation(PAFRAG)simulation *** standard PAFRAG modeling technique is based on the Mott's theory of break-up of idealized cylindrical"ring-bombs",in which the length of the average fragment is a function of the radius and velocity of the shell at the moment of break-up,and the mechanical properties of the *** the newly developed multi-region model,each of the shell region,the break-up is assumed to occur instantaneously,whereas the entire shell is modeled to fragment at multiple times,according to the number of the regions *** to PAFRAG methodology,the required input for both the natural and the controlled fragmentation models including the geometry and the velocity of the shell at moment of break-up had been provided from the hydrocode analyses and validated with available experimental *** newly developed large L/D multi-region PAFRAG model has been shown to accurately reproduce available experimental fragmentation data.

关键词： Explosive fragmentation modeling Natural fragmentation Mott model PAFRAG Fragmentation warhead lethality performance

The impact of magnetic water treatment on salt distribution in a large unsaturated soil column

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international Soil and Water Conservation Research 2017年第4期5卷 253-257页

作者： vladimir Zlotopolski United Research Labs San MarcosCAUSA

The use of saline water for crop production leads to soil ***-treated water(MTW)has been used for many years and has shown promise in leaching some ions from *** the same time,results have been inconsistent and somewhat *** this study,we used large unsaturated columns(diameter 15 cm and length 90 cm)to determine:1)salt distributions at depths of up to 90 cm after adding magnetically-treated,saline water to soil;2)whether MTW could reduce the rate of accumulation of salts(measured by EC)in soil,and;3)whether MTW could increase the leaching effect of soluble salts below root zones compared to *** soil tested had a lower salt content compared to the water,a real-world scenario often faced when farmers elect to switch from higher-cost municipal water sources to ground water sources that have a higher saline *** indicated that the rate of salt accumulation was greater in the control group at the 30–60 cm *** the same time,the salt content at the 90 cm depth was greater in the MTW *** results have shown that MTW changes the distribution of salts between soil layers reducing their content in the upper layers which are more important for agriculture.

关键词： Magnetic water treatment Agriculture Soil irrigation water

Stabilization versus decomposition in alpine ecosystems of the Northwestern Caucasus:The results of a tea bag burial experiment

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Journal of Mountain Science 2018年第8期15卷 1633-1641页

作者： Tatiana G.ELUMEEVA vladimir G.ONiPCHENKO Asem A.AKHMETZHANOVA Mikhail i.MAKAROV Joost A.KEUSKAMP Department of Geobotany Biological FacultyLomonosov Moscow State University119234 Leninskie Gory 1/12MoscowRussia Department of General Soil Science Faculty of Soil ScienceLomonosov Moscow State University119234 Leninskqe Gory 1/12MoscowRussia Ecology 8:Biodiversity Group Utrecht UniversityP.O.Box 80.0563508 TB UtrechtThe Netherlands Netherlands institute of Ecology(NiOO-KNA W) P.O.Box 596700 AB WageningenThe Netherlands

Mountainous areas exhibit highly variable decomposition rates as a result of strong local differences in climate and vegetation type. This paper describes the effect of these factors on two major determinants of the local carbon cycle: litter decomposition and carbon stabilization. in order to adequately reflect local heterogeneity, we have sampled 12 typical plant communities of the Russian Caucasus. in order to minimize confounding effects and encourage comparative studies, we have adapted the widely used tea bag index(TBi) that is typically used in areas with low decomposition. By incubating standardized tea litter for a year, we investigated whether(1) initial litter decomposition rate(k) is negatively correlated with litter stabilization(S) and(2) whether k or S exhibit correlations with altitude and other environmental conditions. Our results show that S and k are not correlated. Altitude, p H, and water content significantly influenced the stabilization factor S, while soil-freezing had no influence. in contrast, none of these factors predicted the decomposition rate k. Based on our data, we argue that collection of decomposition rates alone, as is now common practice, is not sufficient to understand carbon input to soils and can potentially lead to misleading results. Our data on community-specific decomposition and stabilization rates further constrain estimates of litter accumulation in subalpine communities and the potential effects of climate change.

关键词： Litter decomposition Alpine communities Tea bag index Carbon cycle

Synthesis and characterization of BaTiO_3/α-Fe_2O_3 core/shell structure

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Journal of Advanced Ceramics 2019年第1期8卷 133-147页

作者： Suzana FiLiPOVi? Vera P.PAVLOVi? Miodrag MiTRi? Steva LEVi? Neboj?a MiTROVi? Aleksa MARi?i? Branislav VLAHOVi? vladimir B.PAVLOVi? institute of Technical Sciences of Serbian Academy of Sciences and Arts Faculty of Mechanical Engineering University of Belgrade "Vin?a" institute of Nuclear Sciences University of Belgrade Faculty of Agriculture University of Belgrade Faculty of Technical Sciences ?a?ak University of Kragujevac North Carolina Central University NASA University Research Center for Aerospace Device Research and Education and NSF Center of Research Excellence in Science and Technology Computational Center for Fundamental and Applied Science and Education

Multiferroic materials attracted a lot of attention in recent years because of their significant scientific interest and technological applications. The multiferroic core/shell powders have a better connectivity between the phases, resulting in superior dielectric and magneto electric properties. in this study, the influence of preparation condition on structure and properties of BaTiO_3/α-Fe_2 O_3 core/shell composite materials was examined. The five samples were obtained by varying synthesis conditions, such as synthesized method(co-precipitation and sonochemical method) and pH values of solution. XRD and Raman spectroscopy analyses were performed in order to determine phase composition and structural changes within samples. Morphology modifications were examined by SEM and EDS analyses. Finally, effect of structural and microstructural changes on magnetic and electrical properties was detected and explained.

关键词： ceramics electronic materials magnetic materials Raman spectroscopy X-ray diffraction(XRD) ferroelectricity