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PARALLEL HIERARCHICAL MATRIX PRECONDITIONERS FOR THE CURL-CURL OPERATOR

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Journal of Computational Mathematics 2009年第5期27卷 624-641页

作者： Mario Bebendorf Joerg ostrowski Institut fur Numerische Simulation Universitat BonnWegelerstrasse 653115 BonnGermany ABB Switzerland Ltd Corporate ResearchSegelhofstrasse 1 K/P.O.BoxCH-5405 Baden 5 Dattwil

This paper deals with the preconditioning of the curl-curl operator. We use H（curl）- conforming finite elements for the discretization of our corresponding magnetostatic model problem. Jumps in the material parameters influence the condition of the problem. We will demonstrate by theoretical estimates and numerical experiments that hierarchical matrices are well suited to construct efficient parallel preconditioners for the fast and robust iterative solution of such problems.

关键词： Computational electromagnetism Preconditioners Hierarchical matrices Parallelization.

Electronic warfare in the optical band:Main features,examples and selected measurement data

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Defence Technology（防务技术） 2021年第5期17卷 1636-1649页

作者： Roman ostrowski Artur Cywinski Marek Strzelec Polish Naval Academy Navigation and Naval Weapons Faculty69Smidowicza Str.81-127GdyniaPoland Military University of Technology Institute of Optoelectronics2 Gen.S.Kaliskiego Str.00-908WarsawPoland

The paper presents the possibilities of,and methods for,acquiring,analysing and processing optical signals in order to recognise,identify and counteract threats on the contemporary *** main ways electronic warfare is waged in the optical band of the electromagnetic wave spectrum have been formulated,including the acquisition of optical emitter signatures,as well as ultraviolet(UV)and thermal(IR)*** physical parameters and values describing the emission of laser radiation are discussed,including their importance in terms of creating optical ***,it has been shown that in the transformation of optical signals into signatures,only their spectral and temporal parameters can be *** was confirmed in experimental part of the paper,which includes our own measurements of spectral and temporal emission characteristics for three types of binocular laser *** has been further shown that through simple registration and quick analysis involving comparison of emission time parameters in the case of UV signatures in“solar-blind”band,various events can be identified quickly and *** same is true for IR signatures,where the amplitudes of the recorded signal for several wavelengths are *** was confirmed experimentally for UV signatures by registering and then analyzing signals from several events during military exercises at a training ground,namely Rocket Propelled Grenade(RPG)launches and explosions after hitting targets,trinitrotoluene(TNT)explosions,firing armour-piercing,fin-stabilised,discarding sabots(APFSDS)or high explosive(HE)*** final section describes a proposed model database of emitters,created as a result of analysing and transforming the recorded signals into optical signatures.

关键词： Optoelectronics Electronic warfare Optical signature

Systematic Assessment of Synthesized Tri-magnesium Phosphate Powders(Amorphous,Semi-crystalline and Crystalline) and Cements for Ceramic Bone Cement Applications

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Journal of Materials Science & Technology 2015年第5期31卷 437-444页

作者： Nicole ostrowski Vidisha Sharma Abhijit Roy Prashant N.Kumta Department of Bioengineering University of Pittsburgh Center of Complex Engineered Multifunctional Materials University of Pittsburgh Department of Chemical and Petroleum Engineering University of Pittsburgh Department of Mechanical Engineering and Materials Science University of Pittsburgh

Magnesium phosphate cements have come under investigation in recent years for use as an alternative to calcium phosphate cements for bone void repair *** indicates that magnesium phosphate cements obtain higher initial strengths after cement reaction and resorption in more clinically appropriate time frames than commercially available calcium phosphate *** this study,amorphous,partially amorphous and crystalline tri-magnesium phosphate powders were synthesized via an aqueous precipitation reaction with subsequent thermal treatment,and characterized using techniques such as X-ray diffraction and Fourier transform infrared *** materials were assessed for their functionality in cementing reaction with a 3.0 mol/L,pH 7.0 ammonium phosphate solution,including setting time and pH evolution in phosphate buffered saline *** indicated that the amorphous and semi-crystalline tri-magnesium phosphate powders were highly reactive with the setting solution but resulted in mechanically weak cements,while the crystalline tri-magnesium phosphate powder reacted efficiently with the cement solution and were mechanically strong following the cement reaction.X-ray diffraction and scanning electron microscopy analyses indicated significant changes in the phase composition and morphology of the cements following incubation in phosphate buffered *** were perceived to be detrimental to the integrity of the amorphous and semi-crystalline tri-magnesium phosphate derived cements but not to those created with fully crystalline tri-magnesium *** crystalline tri-magnesium phosphate material resulted in the most functional cement as this embodiment displayed the most clinically relevant setting time as well as the highest mechanical resilience and neutral pH during incubation in saline solution rendering them potentially viable as bone void fillers.

关键词： Amorphous magnesium phosphate Tri-magnesium phosph

Assessment of internal defects of hardfacing coatings in regeneration of machine parts

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Journal of Central South University 2018年第5期25卷 1144-1153页

作者： Jerzy JOZWIK Krzysztof DZIEDZIC Ireneusz USYDUS Dawid ostrowski Grzegorz M KROLCZYK Faculty of Mechanical Engineering Lublin University of Technology Electrical Engineering and Computer Science Faculty Lublin University of Technology Institute of Technical Sciences and Aviation State School of Higher Education Faculty of Mechanical Engineering Opole University of Technology

This paper presents the use of computed tomography for the evaluation of hardfacing. The method used in this research is hardfacing by tungsten inert gas using alloy wires of wear resistant layers. This paper discusses the latest materials used for hardfacing and their application. It characterizes the defects of obtained hardfacing and impact of the type of wire on the concentration of defects. It further, the basic mechanical properties of coatings were determined. The results are subjected to qualitative and quantitative analysis. The smallest average percentage of defects in relation to the overall surface is observed for the hardfacing EL-600 HB, which amounts to 1.5%. The highest average percentage of defects in relation to the overall surface is observed for the hardfacing EL-500 HB, which amounts to 7.2%. The chemical composition of hardfacing has been presented.

关键词： hardfacing coating tomography welding defects

Assessing mowing intensity:A new index incorporating frequency,type of machinery,and technique

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Grassland Research 2024年第3期3卷 264-274页

作者： Margarita Hartlieb Sebastian Raubitzek Johanna L.Berger Michael Staab Juliane Vogt Manfred Ayasse Andreas ostrowski Wolfgang Weisser Nico Blüthgen Ecological Networks Department of BiologyTechnical University of DarmstadtDarmstadtGermany SBA-Research ViennaAustria Natura 2000-Station Unstrut-Hainich/Eichsfeld Wildtierland Hainich gGmbHHörselberg-HainichGermany Institute of Evolutionary Ecology and Conservation Genomics Ulm UniversityUlmGermany Heinz Nixdorf Chair for Distributed Information Systems Faculty of Mathematics and Computer ScienceFriedrich Schiller UniversityJenaGermany Department of Life Science Systems School of Life SciencesTechnical University of MunichTerrestrial Ecology Research GroupFreisingGermany

Background:Only a few decades ago,colorful,small-scale,heterogeneous,and species-rich hay meadows or extensive pastures were common,but have often been replaced by species-poor,uniform,large-scale multicut *** advancements and improved efficiency in grassland management have come at the cost of ***:In Germany,150 grassland plots have been investigated since *** these extensive data,we propose a new compound index for estimating the site-specific mowing intensity in order to facilitate assessment of the impact of mowing intensity on biodiversity and ecosystem *** index integrates the various qualitative components of mowing machine type,mowing height and use of a conditioner,with the annual number of ***:The newly proposed index achieves a much finer gradation of mowing intensity compared to the previous quantification based on the number of cuts ***,a decrease in plant and arthropod species was observed at higher mowing ***:The proposed mowing intensity index offers enhanced precision in calculations and can easily be integrated into assessments of land-use intensity in ***,it could serve as a basis for providing subsidies to farmers,who adopt low-impact mowing practices.

关键词： applications conditioner mower mowing height number of cuts species richness

信息技术和电子建筑——一项技术突破,一场技术竞赛或一项商业范例

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信息技术和电子建筑——一项技术突破,一场技术竞赛或一项商业范例

勘察设计企业信息化建设研讨会

作者： Lydia Kiroff Peter ostrowski UNITEC理工学院

信息技术对知识社会的发展所起到的影响非常深远。在人类智力的创造性被高度评价的时代,信息技术是一项强有力的工具,使得观点和理念的分析和发展成为可能。减少客户简单劳动的系统,鼓励更深入的探索,培养创造精神,使得人们能够做以往... 详细信息

信息技术对知识社会的发展所起到的影响非常深远。在人类智力的创造性被高度评价的时代,信息技术是一项强有力的工具,使得观点和理念的分析和发展成为可能。减少客户简单劳动的系统,鼓励更深入的探索,培养创造精神,使得人们能够做以往不可企及的事情。信息技术和团队合作二者紧密结合在一起,达到了更高的共同目标,并使其成为组织行为的关键因素。特别对于 AEC（设计,施工和建筑）产业而言尤其如此。由于联网计算机和多媒体设备的广泛应用,该产业正在经历巨大的变革。我们的研究集中在信息技术及其对建筑设计环境的影响。本文将分析最近兴起的趋势,这些趋势将包括建筑设计事务所在国内和国际项目上的合作（事务所,地方或地区性事务所的建筑专家,负责项目合同资料和项目合同管理的所谓记录建筑师）。这些趋势使得使用诸如先进数字化通信和前所未有的项目网络-或者项目网站-的新技术成为必需,同时,基于网络的建筑学的产生成为必然。高度先进的建筑设计环境围绕内部网,外部网,互联网以及视频会议系统建立起来。从而,建筑设计,商业管理和团队合作通过计算机技术得以整合,并贯穿建筑的整个寿命周期的各个阶段:从传统设计和施工阶段到自动设备管理阶段,再到最终的拆除阶段。

关键词：知识经济 AEC 产业合作式建筑设计外部网团队合作和信息技术的结合

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欧几里得和巴拿赫空间内方程的解法

低燃速的端羧基聚丁二烯丙烯腈(CTBN)推进剂

1988年

作者：奥斯特洛夫斯基（ostrowski A.M.）黎　益等译

书名原文:Solution of equations in Euclidean and Banach spaces:本书介绍了非线性方程和方程组解法的基本理论与成果。

ISBN: (纸本)7561400675

书名原文:Solution of equations in Euclidean and Banach spaces:本书介绍了非线性方程和方程组解法的基本理论与成果。

关键词：数理科学和化学数学计算数学

来源：汇雅图书（南通市图书馆... 评论

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固体火箭技术 1984年第1期 33-40页

作者： P.P.ostrowski C.Gotzmer 罗文明

对端羧基聚丁二烯丙烯睛（CTBN）液体共聚物为粘合剂的极低燃速的复合固定推进剂进行了论证。本计划的目的是,研制一种用于燃气发生器的（StarterCartridge）、压力在70公斤/厘米2（100磅/英寸2）下,燃速指标为1.78毫米/秒（0.070英寸/... 详细信息

对端羧基聚丁二烯丙烯睛（CTBN）液体共聚物为粘合剂的极低燃速的复合固定推进剂进行了论证。本计划的目的是,研制一种用于燃气发生器的（StarterCartridge）、压力在70公斤/厘米2（100磅/英寸2）下,燃速指标为1.78毫米/秒（0.070英寸/秒）的推进剂。选择了双环氧交链系统的低丙烯睛 CTBN 粘合剂,因为它的老化性能和工艺性能较之一般的粘合剂材料优越。在改进的 MK6气体发生器装置中,用浇注单孔圆柱形的、端面包复和外圆柱面包复的推进剂药柱进行弹道性能评定。用50%双级配的过氯酸胺、30%CTBN 粘合剂和20%装填密度高的硝基胍组成的推进剂配方成功地满足了设计要求,在要求的压力与温度25℃（77°F）下,达到了1.70毫米/秒（0.067英寸/秒）的燃速指标。当压力在35公斤/厘米2（500磅/英寸2）到70公斤/厘米2（1000磅/英寸2）范围内,温度在-54℃和74℃之间时,所测得的温度敏感系数π=0.36%/℃（0.20%/°F）。通过初步的力学性能和物理性能试验表明,此种类型的药柱设计在工作条件下,是合格的。因此,这种推进剂用于各种低燃速的场合似乎是有吸引力的。

关键词：推进剂混合端羧基聚丁二烯燃速推进剂药柱 CTBN

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非洲一个偏僻地区孕妇乳母的营养状况

非洲一个偏僻地区孕妇乳母的营养状况