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Spatiotemporal modeling of mid-infrared photoluminescence from terbium(Ⅲ) ion doped chalcogenide-selenide multimode fibers 被引量:1
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作者 Slawomir Sujecki Lukasz sojka +5 位作者 Zhuoqi Tang Dinuka Jayasuriya David Furniss Emma Barney Trevor Benson Angela Seddon 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第11期1157-1163,共7页
A numerical model was developed to study the time dynamics of photo luminescence emitted by Tb^3+doped multimode chalcogenide-selenide glass fibers pumped by laser light at approximately 2μm.The model consists of a s... A numerical model was developed to study the time dynamics of photo luminescence emitted by Tb^3+doped multimode chalcogenide-selenide glass fibers pumped by laser light at approximately 2μm.The model consists of a set of partial differential equations(PDEs),which describe the temporal and spatial evolution of the photon density and level populations within the fiber.In order to solve numerically the PDEs a method of lines was applied.The modeling parameters were extracted from measurements and from data available in the literature.The numerical results obtained support experimental observations.In particular,the developed model reproduces the discrepancies that are observed between the photoluminescence decay curves obtained from different points along the fiber.The numerical analysis was also used to explain the source of these discrepancies. 展开更多
关键词 CHALCOGENIDE glass fiber Numerical modeling PHOTOLUMINESCENCE MID-INFRARED light Rare earths
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An Artificial Heart System for Testing and Evaluation of Cardiac Pacemakers
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作者 Martin Augustynek Jan Kubicek +5 位作者 Jaroslav Thomas Marek Penhaker Dominik Vilimek Michal Strycek Ondrej sojka Antonino Proto 《Computers, Materials & Continua》 SCIE EI 2022年第12期6269-6287,共19页
The usability assessment of a pacemaker is a complex task where the dedicated programmer for testing programmed algorithms is necessary.This paper provides the outcomes of development and complex testing of the artifi... The usability assessment of a pacemaker is a complex task where the dedicated programmer for testing programmed algorithms is necessary.This paper provides the outcomes of development and complex testing of the artificial cardiac system to evaluate the pacemaker’s functionality.In this work,we used the modular laboratory platform ELVIS II and created graphical user interface in LabVIEW programming environment.The electrical model of the heart allows signals generation(right atrium,right ventricle)and the monitoring of the stimulation pulses.The LabVIEW user interface allows to set the parameters of the generated signals and the simulation of the cardiac rhythm disorders as well as the monitoring and visualization of the pacemaker behavior in real-time.The results demonstrate the capability of proposed system to evaluate the paced and sensed pulses.The proposed solution allows the scientists to test the behavior of any cardiac pacemaker for its pre-programmed settings and pacing mode.In addition,the proposed system can simulate various disorders and test cardiac pacemakers in different working modes. 展开更多
关键词 Artificial heart cardiac conduction system electrical cardiac stimulation PACEMAKER
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Tracing mechanism of optically and thermally stimulated luminescence in Lu2O3:Tb,M(M=Hf,Zr,Ti)ceramic storage phosphors
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作者 Malgorzata sojka Dagmara Kulesza +2 位作者 Paulina Bolek Joanna Trojan-Piegza Eugeniusz Zych 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第11期1170-1175,共6页
A series of energy storage phosphors,Lu2O3:Tb,M(M=Hf,Zr,Ti),were investigated by means of photoand thermoluminescence techniques to compare the effect of the co-dopant from the same group of periodic table of elements... A series of energy storage phosphors,Lu2O3:Tb,M(M=Hf,Zr,Ti),were investigated by means of photoand thermoluminescence techniques to compare the effect of the co-dopant from the same group of periodic table of elements on charge carriers trapping capability and trap parameters.Most of the investigated processes were tracked individually for the Tb3+in the two different metal sites offered by the Lu2O3 host-noncentrosymmetric C2 and centrosymmetric C3i.It is proved that both Tb3+ions participate in hole trapping and electrons are immobilized in traps whose depths are defined by the codopant.Deepest traps,~1.79 eV,appear upon Ti addition,while Zr and Hf generate traps of very similar,~1.40-1.44 eV,depths.The stored energy may be released not only by means of thermal stimulation but also upon the impact of optical photons.Light from the 390-430 nm range of wavelengths was found the most efficient in the latter process.Also deep red radiation of 780 nm releases most of the trapped electrons in Zr/Hf co-doped ceramics but is much less effective in the case of Tb,Ti material.Consistent scheme of electronic levels engaged in charge carriers trapping and subsequent generation of thermoand optically stimulated luminescence was constructed. 展开更多
关键词 Storage PHOSPHORS LU2O3 THERMOLUMINESCENCE Optically stimulated luminescence RARE earths
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Customized Online Aggregation &Summarization Tool for Environmental Rasters (COASTER)
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作者 Daniel J. Weiss Katie Gibson +2 位作者 Charles sojka Jennifer W. Sheldon Robert L. Crabtree 《Journal of Geographic Information System》 2012年第6期530-541,共12页
The Customized Online Aggregation & Summarization Tool for Environmental Rasters (COASTER) system (www.COASTERdata.net) was developed by Yellowstone Ecological Research Center (YERC) (www.yellowstoneresearch.org) ... The Customized Online Aggregation & Summarization Tool for Environmental Rasters (COASTER) system (www.COASTERdata.net) was developed by Yellowstone Ecological Research Center (YERC) (www.yellowstoneresearch.org) in response to the information needs of end-user communities interested in decision-support for natural resource management. The purpose of COASTER is to greatly simplify the process of creating predictor datasets for research exploring environmental impacts driven by climate change, land-use activities, disturbance, and invasive spread. COASTER achieves this goal by providing users with a web-based system for processing environmental (gridded, raster) datasets, using a set of standardized functions, to create output customized to meet their analytical needs. In doing so, COASTER effectively translates large and cumbersome datasets into user-specified information useful for parameterizing statistical models and for visualizing spatial and temporal patterns within environmental datasets. The COASTER system currently contains over 10 terabytes of climate data from several sources. These datasets have daily temporal resolutions, spatial resolutions ranging from 1km to 330km, and temporal extents ranging from 30 to 64 years (1948-2011). COASTER datasets are primarily limited to North America, but gridded datasets from other regions can easily be added to the system. Variables within the climatic datasets available on COASTER include metrics quantifying temperature, precipitation, shortwave radiation, vapor pressure deficit, humidity, and wind conditions. Notable features of COASTER include a conceptually simple yet flexible set of functions capable of producing a wide range of outputs, a design applicable to many types of raster datasets, and results formatted for seamless integration within most GIS and remote sensing software packages. 展开更多
关键词 GEOGRAPHIC Information RETRIEVAL ONLINE Application Remote GEOGRAPHIC Data Processing
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Evaluating indicators of human well-being for ecosystem-based management
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作者 Sara Jo Breslow Margaret Allen +17 位作者 Danielle Holstein Brit sojka Raz Barnea Xavier Basurto Courtney Carothers Susan Charnley arah Coulthard Nives Dolsak Jamie Donatuto Carlos Garcia-Quijano Christina C.Hicks Arielle Levine Michael B.Masci Karma Norman Melissa Poe Terre Satterfield Kevin St.Martin Phillip S.Levin 《Ecosystem Health and Sustainability》 SCIE 2017年第12期2-19,共18页
Introduction:Interrelated social and ecological challenges demand an understanding of how environmental change and management decisions affect human well-being.This paper out-lines a framework for measuring human well... Introduction:Interrelated social and ecological challenges demand an understanding of how environmental change and management decisions affect human well-being.This paper out-lines a framework for measuring human well-being for ecosystem-based management(EBM).We present a prototype that can be adapted and developed for various scales and contexts.Scientists and managers use indicators to assess status and trends in integrated ecosystem assessments(IEAs).To improve the social science rigor and success of EBM,we developed a systematic and transparent approach for evaluating indicators of human well-being for an IEA.Methods:Our process is based on a comprehensive conceptualization of human well-being,a scalable analysis of management priorities,and a set of indicator screening criteria tailored to the needs of EBM.We tested our approach by evaluating more than 2000 existing social indicators related to ocean and coastal management of the US West Coast.We focused on two foundational attributes of human well-being:resource access and self-determination.Outcomes and Discussion:Our results suggest that existing indicators and data are limited in their ability to reflect linkages between environmental change and human well-being,and extremely limited in their ability to assess social equity and justice.We reveal a critical need for new social indicators tailored to answer environmental questions and new data that are disaggregated by social variables to measure equity.In both,we stress the importance of collaborating with the people whose well-being is to be assessed.Conclusion:Our framework is designed to encourage governments and communities to carefully assess the complex tradeoffs inherent in environmental decision-making. 展开更多
关键词 Human well-being INDICATORS ecosystem-based management integrated ecosystem assessment resource access SELF-DETERMINATION
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The Impact of pH and Air on the Phospholipid Nanostructure Surface 被引量:1
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作者 M. sojka Z. Pawlak 《Open Journal of Orthopedics》 2021年第12期392-398,共7页
Phospholipids (PLs) in the form of nanostructures are widely employed as a lubricant and antimicrobial agent. The cartilage (AC) surface was characterized using wettability test fresh and depleted AC samples. Cartilag... Phospholipids (PLs) in the form of nanostructures are widely employed as a lubricant and antimicrobial agent. The cartilage (AC) surface was characterized using wettability test fresh and depleted AC samples. Cartilage wet surface exposure to air causes increase </span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">in </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">surface wettability from 0 to 104 degrees. Effect is explained by flip-flop of the PLs molecules in membrane. The hydrophilic and hydrophobic character of cartilage was determined. Microscopic image of PLs bilayers adsorbed on the surface of pleural tissues and human stomach will be compared with cartilage tissue. 展开更多
关键词 PLs Bilayers Wettability PLs Flip-Flop PLEURAL Cartilage Surface Human Stomach Tissue
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不定原点喷嘴射流中流体物理的实验研究(英文) 被引量:1
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作者 束方军 Michael W.Plesniak Paul E.sojka 《实验力学》 CSCD 北大核心 2007年第3期277-284,共8页
为了能够更好地了解不定源喷嘴(indeterminate origin nozzle)射流中的物理过程,本文应用平面激光诱导荧光技术对一个大尺度的水射流进行了实验研究。流场显示的实验结果表明不定源喷嘴在射流的剪切层引入了蘑菇形反向旋转的涡对。这些... 为了能够更好地了解不定源喷嘴(indeterminate origin nozzle)射流中的物理过程,本文应用平面激光诱导荧光技术对一个大尺度的水射流进行了实验研究。流场显示的实验结果表明不定源喷嘴在射流的剪切层引入了蘑菇形反向旋转的涡对。这些涡的矢量方向与射流方向相同或相反,被称为流向涡(streamwise vortex)。由于射流中存在开尔文-亥姆霍兹不稳定,每当一个横向涡(spanwise vortex,即涡的矢量方向与射流方向垂直)从喷嘴脱流时会产生瞬时的低压,该瞬时低压促使向内发展的流向涡对在喷嘴的凹槽处生成。这些涡对在向下游流动的过程中会重组并在喷嘴的尖峰面生成向外发展的涡对。这些流向涡极大地影响了射流的发展。流向涡与横向涡的相互作用促使射流更早地发展成为湍流。由于流向涡同时也在射流中引入了径向的剪切流动,因此导致了更多的湍流生成从而增强了射流与周围流体的混合。 展开更多
关键词 不定源喷嘴 射流 流向涡 被动控制
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