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Time-Reversal UWB Positioning Beacon for Railway Application

Wireless Engineering and Technology 2013年第1期4卷 28-39页

作者： Bouna Fall Fouzia Elbahhar Marc Heddebaut Atika Rivenq Université Lille Nord de France Lille France Institut Francais des Sciences et Technologies des Transports de L’aménagement et des Réseaux (IFSTTAR) Laboratoire Electronique Ondes et Signaux Pour les Transports (LEOST) Villeneuve d’Ascq France Université Lille Nord de France Lille France Institut Francais des Sciences et Technologies des Transports de L’aménagement et des Réseaux (IFSTTAR) Laboratoire Electronique Ondes et Signaux Pour les Transports (LEOST) Villeneuve d’Ascq France Université de Valenciennes et du Hainaut-Cambrésis (UVHC) Institut D’électronique de Microélectronique et de Nanotechnologie (IEMN) Département Opto-Acousto-Electronique (DOAE) Valenciennes France centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) Villeneuve d’Ascq France Université Lille Nord de France Lille France Université de Valenciennes et du Hainaut-Cambrésis (UVHC) Institut D’électronique de Microélectronique et de Nanotechnologie (IEMN) Département Opto-Acousto-Electronique (DOAE) Valenciennes France centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) Villeneuve d’Ascq France

This paper studies a new positioning beacon for railway transport using Ultra Wideband (UWB) radio and Time Reversal (TR) techniques. UWB radio has the potential to offer a good level of performance in terms of localization accuracy. Time Reversal channel pre-filtering facilitates signal detection and also helps increasing the received energy in the targeted area. In this paper, we evaluate the characteristics of TR technique in terms of temporal focusing. The theoretical and simulation results for Power Delay Profile, equivalent channel model and focusing gain of TR-UWB are given. We analyze the contribution of Time Reversal associated with UWB technology to enhance the localization resolution. The IEEE 802.15.3achannel models are used to evaluate the performance of this system. In terms of localization error, the theoretical and simulation results show that TR-UWB technique delivers improved performance over the UWB localization approach.

关键词： UWB Time Reversal Focusing Gain Channel Model Power Delay Profile TDOA Localization Error

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Nine requirements for the origin of Earth’s life:Not at the hydrothermal vent, but in a nuclear geyser system

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Geoscience Frontiers 2019年第4期10卷 1337-1357页

作者： Shigenori Maruyama Ken Kurokawa Toshikazu Ebisuzaki Yusuke Sawaki Konomi Suda M. Santosh Earth-Life Science Institute Tokyo Institute of Technology2-12-1 O-okayamaMeguro-kuTokyo 152-8551Japan Kochi University Kochi 780-8520Japan Novosibirsk State University Pirogova 1630090Russia Genome Evolution Laboratory National Institute of Genetics1111 YataMishimaShizuoka 411-8540Japan RIKEN 2-1 HirosawaWakoSaitama351-0198Japan Department of Earth and Planetary Sciences Graduate School of Science and EngineeringTokyo Institute of Technology2-12-1 OokayamaMeguro-kuTokyo 152-8550Japan Department of Earth Science and Astronomy Graduate School of Arts and Sciences The University of Tokyo3-8-1 KomabaMeguro-kuTokyo 153-8902Japan Geomicrobiology Research Group Institute for Geo-Resources and EnvironmentNational Institute of Advanced Industrial Science and Technology (AIST)Central 71-1-1 HigashiTsukubaIbaraki 305-8567Japan centre for Tectonics Resources and ExplorationDepartment of Earth SciencesUniversity of AdelaideSA 5005Australia School of Earth Sciences and Resources China University of Geosciences (Beijing)29 Xueyuan RoadBeijing 100083China

The origin of life on Earth remains enigmatic with diverse models and *** we discuss essential requirements for the first emergence of life on our planet and propose the following nine requirements:(1)an energy source(ionizing radiation and thermal energy);(2)a supply of nutrients(***.);(3)a supply of life-constituting major elements;(4)a high concentration of reduced gases such as CH4,HCN and NH3;(5)dry-wet cycles to create membranes and polymerize RNA;(6)a non-toxic aqueous environment;(7)Na-poor water;(8)highly diversified environments,and(9)cyclic conditions,such as dayto-night,hot-to-cold *** on these nine requirements,we evaluate previously proposed locations for the origin of Earth’s life,including:(1)Darwin’s"warm little pond",leading to a"prebiotic soup"for life;(2)panspermia or Neo-panspermia(succession model of panspermia);(3)transportation from/through Mars;(4)a deepsea hydrothermal system;(5)an on-land subduct ion-zone hot spring,and(6)a geyser systems driven by a natural nuclear *** conclude that location(6)is the most ideal candidate for the o rigin point for Earth’s life because of its efficiency in continuously supplying both the energy and the necessary materials for life,thereby maintaining the essential"cradle"for its initial *** also emphasize that falsifiable working hypothesis provides an important tool to evaluate one of the biggest mysteries of the universe-the origin of life.

关键词： Origin of Earth's life Nuclear geyser system Emergence and evolution of life Falsifiability

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***-oxidation of N-retinylidene-N-retinylethanolamine in vitro by high-energy visible light

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Annals of Eye Science 2018年第1期 430-430页

作者： Marie-Christine Lambert Mathieu Ouellette Élodie Boisselier Patrick J.Rochette centre Universitaire d’Ophtalmologie Hôpital du Saint-SacrementCHU de QuébecCanada Axe Médecine Régénératrice Centre de recherche du CHU de QuébecHôpital du Saint-SacrementCHU de QuébecCanada Département d’ophtalmologie et d’ORL-CCF Facultéde médecineUniversitéLavalQuébecCanada

Background:Age-related macular degeneration(AMD)is the second Canadian cause in visual *** is characterized by the death of photoreceptors and retinal pigmented epithelium(RPE)in the macular region of the retina,leading to the loss of central *** studies suggest an association between lifetime sun exposure and the probability to develop AMD even though mechanisms are *** is made of about 30%of high-energy visible(HEV)light(blue light),the most energetic wavelength reaching the *** wavelengths can be absorbed by lipofuscin,an age pigment accumulating in RPE *** principal component is N-retinylidene-N-retinylethanolamine(A2E).Many research teams showed that absorption of HEV light by A2E in RPE cells at non-physiological doses produces free radicals and leads to cell *** earlier work shows that when A2E-loaded RPE cells are irradiated with HEV light at physiological doses,the same light does not lead to oxidative stress as measured by telomere and mitochondrial *** hypothesis is that HEV light,at physiological doses,modify or convert A2E in derived produces,inhibiting its photo-oxidant ***:In vitro,we irradiated A2E with HEV light with or without antioxidants and with varying irradiation regimen to observe the UV-Visible spectrum of *** cellulo,we loaded ARPE-19 cells with A2E and irradiated cells at physiological levels for 4 consecutive *** then observed A2E fluorescence using a fluorescence microscope with nucleus counterstaining with ***:HEV light leads to the disappearance of A2E characteristic UV-Visible spectrum and the apparition of a new product suggesting that HEV light modifies *** oxidation and irradiation regimen seem to have an impact in A2E’s conversion by HEV *** observed and progressive diminution of A2E fluorescence in cellulo during physiological ***:The loss of A2E photo-oxidation capacities by HEV light seems to

关键词： Age-related macular degeneration(AMD) A2E degradation blue light retinal pigmented epithelium(RPE) cellular toxicity

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Tunable optical topological transitions of plasmon polaritons in WTe_(2) van der Waals films

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Light(Science & Applications) 2023年第9期12卷 1807-1817页

作者： Yuangang Xie Chong Wang Fucong Fei Yuqi Li Qiaoxia Xing Shenyang Huang Yuchen Lei Jiasheng Zhang Lei Mu Yaomin Dai Fengqi Song Hugen Yan State Key Laboratory of Surface Physics Key Laboratory of Micro and NanoPhotonic Structures(Ministry of Education)and Department of PhysicsFudan University200433 ShanghaiChina centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement(MOE)School of PhysicsBeijing Institute of Technology100081 BeijingChina Beijing Key Lab of Nanophotonics&Ultrafine Optoelectronic Systems School of PhysicsBeijing Institute of Technology100081 BeijingChina National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced Microstructuresand College of PhysicsNanjing University210093 NanjingChina Atom Manufacturing Institute(AMI) 211805 NanjingChina Center for Superconducting Physics and Materials National Laboratory of Solid State Microstructures and Department of PhysicsNanjing University211805 NanjingChina

Naturally existing in-plane hyperbolic polaritons and the associated optical topological transitions,which avoid the nano-structuring to achieve hyperbolicity,can outperform their counterparts in artificial *** plasmon polaritons are rare,but experimentally revealed recently in WTe_(2)van der Waals thin *** from phonon polaritons,hyperbolic plasmon polaritons originate from the interplay of free carrier Drude response and interband transitions,which promise good intrinsic ***,tunable in-plane hyperbolic plasmon polariton and its optical topological transition of the isofrequency contours to the elliptic topology in a natural material have not been *** we demonstrate the tuning of the optical topological transition through Mo doping and *** optical topological transition energy is tuned over a wide range,with frequencies ranging from 429 cm^(−1)(23.3 microns)for pure WTe_(2)to 270 cm^(−1)(37.0 microns)at the 50%Mo-doping level at 10 ***,the temperature-induced blueshift of the optical topological transition energy is also revealed,enabling active and reversible ***,the localized surface plasmon resonance in skew ribbons shows unusual polarization dependence,accurately manifesting its topology,which renders a reliable means to track the topology with far-field *** results open an avenue for reconfigurable photonic devices capable of plasmon polariton steering,such as canaling,focusing,and routing,and pave the way for low-symmetry plasmonic nanophotonics based on anisotropic natural materials.

关键词： topological transitions polar

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Motorists’Perceptions and Attitudes towards Ethanol Blended Fuel in Zimbabwe

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Journal of energy and Power Engineering 2019年第2期13卷 68-79页

作者： Decide Mabumbo Paramu Mafongoya centre for the Advancement of Scholarship University of PretoriaPrivate Bag x20Hatfield 0027South Africa School of Agriculture Earth and Environmental Sciences: University of KwaZulu-NatalPietermaritzburg 3209South Africa

Most developing and developed countries have enacted mandatory legislation for use of biofuels(bioethanol)in the transport *** most developing countries,the use of biofuels meant to increase energy security,save foreign currency,mitigate climate change,create jobs and rural ***,motorists have limited knowledge on blended *** study seeks to investigate the level of awareness and prevailing attitudes of motorists in Zimbabwe where a mandatory ethanol blending policy was recently *** study uses data derived from 200 respondents,to whom a questionnaire was *** major challenge faced by motorists is the lack of sufficient information on ethanol blends in general including how they can get their engines modified to take high ethanol *** 63.1% were not clear about the technical attributes of ethanol blended fuel especially as it relates to engine ***,some motorists experienced a number of problems ranging from poor idling(36%),lack of power(19.5%)and difficulties with engine starting(16.5%).Despite all these complaints,54% of the respondents generally exhibit a positive attitude towards ethanol blended fuel and 60.3% said that they were keen to recommend blended fuel to other *** appropriate institutional,legal and policy framework that supports massive awareness campaigns for use of bioethanol for the transport sector can go a long way to dispel negative perceptions associated with ethanol blends.

关键词： Biofuels motorists knowledge attitude perceptions

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青藏高原地区能量水分循环:地表能量平衡和湍流热通量(英文)

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地球科学进展 2006年第12期21卷 1224-1236页

作者：苏中波张廷马耀明贾立文军 International Institute for Geo-Information Science and Earth Observation ITC Enschede7500AA the Netherlands 天津市政工程局科学技术部天津300022 中国科学院青藏高原研究所北京100085 Alterra Green World Research Wageningen University and Research centre Wagenigen 6700AA the Netherlands 中国科学院寒区旱区环境与工程研究所甘肃兰州730000

文章给出了青藏高原能量水分循环研究的概况和总结,着重估计了能量平衡各分项和湍流热通量等。在能量平衡的计算基础上,尽管能量不平衡的原因解释仍有争论并且没有解决,但我们揭示了GAME/Tibet试验观测资料中能量不平衡现象。我们发现... 详细信息

文章给出了青藏高原能量水分循环研究的概况和总结,着重估计了能量平衡各分项和湍流热通量等。在能量平衡的计算基础上,尽管能量不平衡的原因解释仍有争论并且没有解决,但我们揭示了GAME/Tibet试验观测资料中能量不平衡现象。我们发现估算的潜热通量比实际观测的要高许多。然而,根据能量平衡假设的计算结果和SEBS的估算一致性很好。在此基础上可以归纳出差异主要由GAME/Tibet试验观测资料中能量不平衡引起,潜热通量的实际观测可能偏小。

关键词：能量水分循环青藏高原地区能量平衡通流通量

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Studies of laser-plasma interaction physics with low-density targets for direct-drive inertial confinement schemes

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Matter and Radiation at Extremes 2019年第4期4卷 15-22页

作者： V.Tikhonchuk Y.J.Gu O.Klimo J.Limpouch S.Weber ELI-Beamlines Institute of PhysicsAcademy of Sciences of the Czech Republic18221 PragueCzech Republic centre Lasers Intenses et Applications University of Bordeaux–CNRS–CEATalence 33405France Institute of Plasma Physics of the CAS Za Slovankou 1782/318200 PragueCzech Republic FNSPE Czech Technical University in Prague11519 PragueCzech Republic

Comprehensive understanding and possible control of parametric instabilities in the context of inertial confinement fusion (ICF) remains achallenging task. The details of the absorption processes and the detrimental effects of hot electrons on the implosion process require as mucheffort on the experimental side as on the theoretical and simulation side. This paper describes a proposal for experimental studies on nonlinearinteraction of intense laser pulses with a high-temperature plasma under conditions corresponding to direct-drive ICF schemes. We propose todevelop a platform for laser-plasma interaction studies based on foam targets. Parametric instabilities are sensitive to the bulk plasma temperatureand the density scale length. Foam targets are sufficiently flexible to allow control of these parameters. However, investigationsconducted on small laser facilities cannot be extrapolated in a reliable way to real fusion conditions. It is therefore necessary to performexperiments at a multi-kilojoule energy level on medium-scale facilities such asOMEGAor SG-III. An example of two-plasmon decay instabilityexcited in the interaction of two laser beams is considered.

关键词： interaction details excited

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Performance Evaluation of a Maize Cob Thresher

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Journal of Agricultural Science and Technology(A) 2019年第1期9卷 64-70页

作者： Adeyi Abdulrasaq Mashood Willoughby Fouad Ayinde Shehu Muhammed Yusuf Ola Olalekan Abiola Faleye Tope National centre for Agricultural Mechanization(NCAM) Farm Power&Machinery DepartmentKM 20Ilorin-Lokoja High Way IdofianP.M.B.1525Ilorin Kwara StateNigeria

Threshing is one of the most critical parts of post-harvest operation which affects the quality and quantity of maize *** could be done manually or ***,the objective of this study was to evaluate the performance of a maize cob thresher fabricated at National centre for Agricultural Mechanization(NCAM)Ilorin at three different moisture contents and analyze the result using ANOVA and bar chart as statistical *** average values of parameters evaluated at three different stages of moisture content(15.81%,16.79%and 17.10%)of maize cob are as follow:threshing capacity 754.20,737.38 and 720.23 kg/h;threshing efficiency 99.73%,99.63%and 99.16%;cleaning efficiency 89.82%,89.45%and 88.34%;broken grains ratio 0.84%,0.79%and 0.70%;time taken 43,44 and 45 s,*** total amount of maize cob fed into the machine was 9 kg in three replicates for each of the moisture content and the average values of threshed maize of 8.08,8.05 and 7.95 kg was recovered,*** was significant difference in threshing efficiency,amount of chaffs in the threshed maize and the percentage broken *** 17.10%moisture content,the percentage broken grain ratio was *** high moisture content,more force,energy and time is required to thresh certain amount of maize ***,at minimal moisture content less force and energy is required for maximum ***,considering the previous work on performance evaluation of maize cob thresher,this machine performed satisfactorily and is far better than manual *** machine is effective,efficient,affordable and available for the small and medium scale farmers in Nigeria.

关键词： Maize cob thresher performance evaluation moisture

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Innovative Solutions in Induction Heating for Better energy Efficiency:Presentation of ISIS Project

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Journal of Iron and Steel Research International 2012年第S2期19卷 646-652页

作者： PAYA Bernard GAGNOUD Annie MAUSSION Pascal ROEHR Philippe BREVILLE Thierry NEMER Maroun GOUPIL Christophe Coordinator of ISIS Project EDF R&DEco-Efficiency & Industrial Processes DptCentre des RenardieresF-77818 Morêt sur Loing CedexFrance SIMAP/EPM 1340Rue de la Piscine BP 75F-38402 Saint Martin d'Hères CedexFrance LAPLACE/CODIASE 2.Rue Charles CamichelBP 7122F-31071 Toulouse Cedex 7France FIVES CELES 89bisRue PrincipaleF-68610 LautenbachFrance ATYS CONSULTANTS ZA du pré ROBELIN358 route d'UriageF-38320 HerbeysFrance ARMINES/CEP ZI Les Glaizes5 rue Leon BlumF-91120 Palaiseau France CRISMAT ENSICAEN6Boulevard du Marechal JuinF-14050 CaenFrance

The energy Climate Package is the EU response to the Global Warming *** heating processes can contribute to the energy saving goal:20%saving within *** induction manufacturer already propose many efficient solutions at industrial *** improve induction devices for an always better energy efficiency, EDF R&D set up a French cooperative project called ISIS with a financial support of the French National Research *** objective is to promote induction heating as Best Available Technology(BAT)and to develop innovative solutions to increase its *** ISIS innovations concern the electroheat conversion of induction devices(auto-adaptive multi-coil power supply,low losses coils)and the recovering of fatally lost *** paper shows the mid-term results of this *** control algorithms were successfully tested on a 100 kW 3-coil power supply.A homogenization technique is proposed to model a multi-strand coil.A heat recovery test bench is build and equipped with a PFC control loop to fit with the production fluctuations.

关键词： induction heating energy efficiency multi-coil power supply multi-strand coil energy recovery PFC

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Profiles of HIV-Affected Households in Ghana

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Health 2014年第15期6卷 2004-2013页

作者： Amos Laar Daniel Fiaveh Matilda Laar Sandra Boatemaa James Abugri Angela El-Adas Richard Amenyah Kyeremeh Atuahene Andrew Anthony Adjei Isabella Quakyi centre for Gender Studies and Advocacy University of Ghana Accra Ghana Department of Applied Chemistry and Biochemistry Faculty of Applied Sciences University for Development Studies Navrongo Campus Tamale Ghana Department of Biological Environmental and Occupational Sciences School of Public Health University of Ghana Accra Department of Pathology Korle-Bu Teaching Hospital College of Health Sciences University of Ghana Accra Ghana Department of Population Family & Reproductive Health School of Public Health University of Ghana Accra Ghana Ghana AIDS Commission Accra Ghana Regional Institute for Population Studies University of Ghana Accra Ghana School of Dietetics and Human Nutrition McGill University Montreal Canada

Background: To contribute to a fuller appreciation of Ghana’s HIV epidemic, this paper presents various profiles of the Ghanaian HIV-affected household. To comprehensively tackle the HIV epidemic in Ghana, the profiles would provide stakeholders with ready information for policy formulation. Methods: We used data from a nationally representative survey that measured livelihood activities, household asset wealth, household composition, health, and nutrition variables of 1745 HIV-affected households. From these emerged various profiles. Results: About 50% of the households are headed by females. Households headed by men have an average size of three members, compared to two for female-headed households. There are far more AIDS widows than widowers. The annual death rate among the surveyed households was about 1000 per 100,000-households. Relatively more deaths occurred in male-headed households. Two-thirds of the households were asset poor. Various coping strategies were instituted by the households in reaction to threat of food insecurity. The national prevalence of chronic energy deficiency is 16%. Conclusions: Our data show that age of household head, hosting of a chronically ill member, and average size of household differed by sex of household head. The annual death rate of 1000 per 100,000 households is very high.

关键词： HIV-Affected Households Profiles HIV Ghana

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