Maritime Radar Performance
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New Journal of Physics the Open–Access Journal for Physics
New Journal of Physics The open–access journal for physics On the origin of the fast photoluminescence band in small silicon nanoparticles J Valenta1,6, A Fucikova1, I Pelant2,KKusová˚ 2, K Dohnalová2, A Aleknaviciusˇ 2,5, O Cibulka2, A Fojtík3 and G Kada4 1 Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic 2 Institute of Physics, Academy of Sciences of the Czech Republic, v. v. i., Cukrovarnická 10, 162 53 Prague 6, Czech Republic 3 Faculty of Nuclear Science and Physical Engineering, Czech Technical University in Prague, V Holesoviˇ ckáchˇ 2, 182 00 Praha 8, Czech Republic 4 Agilent Technologies, Mooslackengasse 17, 1190 Vienna, Austria E-mail: [email protected] New Journal of Physics 10 (2008) 073022 (6pp) Received 13 February 2008 Published 11 July 2008 Online at http://www.njp.org/ doi:10.1088/1367-2630/10/7/073022 Abstract. Colloidal suspensions of small silicon nanoparticles (diameter around 2 nm) with fast and efficient ultraviolet–blue photoluminescence (PL) band are fabricated by enhanced electrochemical etching of Si wafers. The detailed study of photoluminescence excitation spectra in a wide range of excitation photon energies (270–420 nm) reveals specific behavior of the Stokes shift of the fast PL band that agrees well with theoretical calculation of optical transitions in small silicon nanocrystals and is distinct from emission of silicon dioxide defects. Efficient photoluminescence (PL) of porous silicon (PSi)—first observed by Canham [1]— provoked intensive research on silicon-based nanocrystalline materials. There are mainly two types of PL emission in Si nanostructures at room temperature. -
Mitigation of Terrestrial Radar Interference in L-Band Spaceborne Microwave Radiometers
Mitigation of Terrestrial Radar Interference in L-Band Spaceborne Microwave Radiometers J.R. Piepmeier and F.A. Pellerano Microwave Instrument Technology Branch NASA's Goddard Space Flight Center Greenbelt, MD 2 1 146 Email: [email protected] Abstract-Terrestrial radars operating in the 1215-1400 MHz Hydros missions [lo]. Given the impacts, three aspects to radio-location and navigation spectrum allocation are important mitigation are proposed: survivability, operability, and excis- for air traffic safety, homeland security, and national defense. For ability; or SOE. Survivability deals with avoiding damage low-frequency observations of soil moisture and ocean salinity, Earth-observing microwave radiometers are allocated Earth- from RFI. This means proper filtering and limiting. A ra- Exploration Satellite Service (EESS) spectrum for operating at diometer achieves operability when it can measure, without 1400-1427 MHz. The proximity of powerful long-range radars to error, the antenna or brightness temperature in the presence of the passive allocation makes observing a challenge. Three aspects interference. Selective receivers operating in quite spectrum of mitigation to RFI are discussed in this paper: survivability, are required for operability. When filtering and frequency operability, and excisability (SOE). Modeling and simulations of NASA's Hydros and Aquarius radiometers were performed selection is not enough to avoid interference, then the RFI to examine the impacts of radar interference. The results are might be excisable. A number of techniques have been pro- applied to the three aspects of mitigation SOE and the affects posed and demonstrated recently [Ill-[14]. These fall into on the radiometer requirements are discussed. three basic categories: temporal, spectral, and statistical - some techniques are a combination of two or more. -
1 Distinct Band Reconstructions in Kagome Superconductor Csv3sb5
Distinct band reconstructions in kagome superconductor CsV3Sb5 Yang Luo1,#, Shuting Peng1,#, Samuel M. L. Teicher2,#, Linwei Huai1,#, Yong Hu1,3, Brenden R. Ortiz2, Zhiyuan Wei1, Jianchang Shen1, Zhipeng Ou1, Bingqian Wang1, Yu Miao1, Mingyao Guo1, M. Shi3, Stephen D. Wilson2 and J.-F. He1,* 1Hefei National Laboratory for Physical Sciences at the Microscale, Department of Physics and CAS Key Laboratory of Strongly-coupled Quantum Matter Physics, University of Science and Technology of China, Hefei, Anhui 230026, China 2Materials Department and California Nanosystems Institute, University of California Santa Barbara, Santa Barbara, California 93106, USA 3Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland #These authors contributed equally to this work. *To whom correspondence should be addressed: [email protected] The new two-dimensional (2D) kagome superconductor CsV3Sb5 has attracted much recent attention due to the coexistence of superconductivity, charge order, topology and kagome physics [1- 33]. A key issue in this field is to unveil the unique reconstructed electronic structure, which successfully accommodates different orders and interactions to form a fertile ground for emergent phenomena. Here, we report angle-resolved photoemission spectroscopy (ARPES) evidence for two distinct band reconstructions in CsV3Sb5. The first one is characterized by the appearance of new electron energy band at low temperature. The new band is theoretically reproduced when the three dimensionality of the charge order [21-23] is considered for a band-folding along the out-of-plane direction. The second reconstruction is identified as a surface induced orbital-selective shift of the electron energy band. Our results provide the first evidence for the three dimensionality of the charge order in single-particle spectral function, highlighting the importance of long-range out-of-plane electronic correlations in this layered kagome superconductor. -
Terahertz Induced Non-Linear Electron Dynamics in Nanoantenna Coated Semiconductors at the Sub-Picosecond Timescale
AN ABSTRACT OF THE DISSERTATION OF Andrew Stickel for the degree of Doctor of Philosophy in Physics presented on August 10, 2016. Title: Terahertz Induced Non-linear Electron Dynamics in Nanoantenna Coated Semiconductors at the Sub-picosecond Timescale Abstract approved: Yun-Shik Lee This dissertation is an exploration of the material response to Terahertz (THz) radiation. Specifically we will explore the ultrafast electron dynamics in the non- perturbative regime in semiconductors that have been patterned with nanoantenna arrays using broadband, high intensity, THz radiation. Three main semiconductor materials will be studied in this work. The first is VO2 which undergoes a phase transition from an insulator, when it is below 67◦ C, to a metal, when it is above 67◦ C. The second and third materials are Si and GaAs which are two of the most commonly used semiconductors. We study the insulator to metal transition (IMT) of VO2 and its response to high field THz radiation. The near room temperature IMT for VO2 makes it a very promising material for electrical and photonic applications. We demonstrate that with high field THz the IMT transition can be triggered. This transition is induced on a sub-cycle timescale. We also demonstrate a THz field dependent reduction in the transition temperature for the IMT when transitioning from both below Tc to above as well as from above Tc to below. This transition is not equal for the above and below cases and leads to a narrowing of the hysteresis curve of the IMT. The thin film Fresnel coefficients, along with a phenomenological model developed for the nanoantenna patterned VO2, are also used to calculate the sheet conductivity of the VO2 sample. -
Disarmament Conference'
University of Nebraska at Omaha DigitalCommons@UNO Kabul Times Digitized Newspaper Archives 7-28-1965 Kabul Times (July 28, 1965, vol. 4, no. 104) Bakhtar News Agency Follow this and additional works at: https://digitalcommons.unomaha.edu/kabultimes Part of the International and Area Studies Commons Recommended Citation Bakhtar News Agency, "Kabul Times (July 28, 1965, vol. 4, no. 104)" (1965). Kabul Times. 1025. https://digitalcommons.unomaha.edu/kabultimes/1025 This Newspaper is brought to you for free and open access by the Digitized Newspaper Archives at DigitalCommons@UNO. It has been accepted for inclusion in Kabul Times by an authorized administrator of DigitalCommons@UNO. For more information, please contact [email protected]. ~!'. - _. .,.. -::'~ _:.~---- ';'- ' . _.: . ---~ _._ ....... :$2:_ 3 ;c: ... ce,,~ -. : ': ': . :; ',-'•.f - . -. ..:. " -' , -.'. -. .: -~. - . - . .. ,: - '. ••.t • - -.:- --.:'~ '~-' ...- '. -. .. -. ." ..- - -- • : : '- . " . .. --- '" .. , , : - - . -... _. :-. -: :-- - . '. ., . -. ~ - ' . .. - . '. , . , · ., .' .- ---. ~ . ,; __ 7-_ ..- • -. - .. - • < ,.., ,- .. :. '.' , . if '. NEWS STALLS . -.... -, . ~ -"- - ~. THE WEATHER "-". .., . KABUL TIMES JULY 27, 1965 Yesterday'S Tempera&are . ~, < • , .'t,. Max, + 31'C, Minimum 12°C· I·,' .: ..~ , Sun sets· today at 6:54 P.DL Belgian En-voy He.r-e.NamedI '- , ,Nasser De'njes VARAIr Force· suD. rjses tomorrow at 5:03 am· - Tomorrow's Outlook: Cloudy ~ -.. KA~UL, 27.~The .' ".' ',' 'Tr'ied To'Bomb His~Re$idence' July Ministry . of 'Foreign Affairs smd :yesterday j VOL. rv,NO. 104 KABUL'WEDNESDAY,. .JULY ·28"(ASA'D:··6~1344;··S.H.) :: .,:, -:'.:'. , . =;:.0 .....- . :"'-, '. '.;-- / . s . .(DPA):~ ~~~~~~_~~~~~ ,_~ ~".~~~.~~~c~,~~:~._.~~.~.~:~~~~~~~~~~~~.~.~_~.~.,~:=.~~.C=E~.A~.!~:! ~.:~~~ '·:.ALExANDRIA, JulY' ·27) that Jean Leroy, .the Belgian Am e' . , .. , .. .. pRESIDENT Gamal Abci~l.Nasser.1?f.t~e uAR has ~tegori. bassado!' in N~w DeIhi, -has been '. , cally d~n1ed th!lt an attelJi:)t~~ been made by aU' force, appointed to act siniultaneously as ·1Ii......· ,. -
A Study of the Fundamental Vibration-Rotation Bands in the Infrared Spectra of St I Bene and Deutero-Stibene
A STUDY OF THE FUNDAMENTAL VIBRATION-ROTATION BANDS IN THE INFRARED SPECTRA OF ST I BENE AND DEUTERO-STIBENE DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By William Howard Haynle, S.F., M*Sc« The Ohio State University 1961 Approved byi «w-<'s i wi[//// Adviser ACKNOWLfcDGLlEHTS It gives me pleasure to acknowledge the help and oooperation extended to me by many persons during the course of this investiga tion* For advice on the theory of molecular structure and sugges tions on the interpretation of the experimental data I am indebted to Professors K* H* Nielsen and E* E* Bell* I am very grateful to Professor J. 0* Lord of the Department of Metallurgy for help in preparing a suitable alloy, and to Professor A* B. Garrett of the Department of Chemistry for advice concerning the chemical proce dures involved in generating the samples. My thanks are due to Mr* William Ward for help in obtaining the data* I am particularly Indebted to Professor R* A* Oetjen for his advice and encouragement over the past five years* Finally, I wish to express my sincere gratitude to Gloria Westphal Haynle who has checked the proof and verified all of the calculations* Her help and encouragement have been invaluable* 0 2 2 1 < > 2 TABLE OF CONTENTS Fag® Introduction ................................ 1 Summary of Theoretical Work ........................ 5 Experimental W o r k ............................................... 18 Analysis of the Absorption Spectra of SbH and SbD_ ........... 26 3 3 Appendix......................................................... 55 Bibliography .................................................. -
A Comprehensive Review on Food Applications of Terahertz Spectroscopy and Imaging Leili Afsah-Hejri , Parvaneh Hajeb, Parsa Ara, and Reza J
A Comprehensive Review on Food Applications of Terahertz Spectroscopy and Imaging Leili Afsah-Hejri , Parvaneh Hajeb, Parsa Ara, and Reza J. Ehsani Abstract: Food product safety is a public health concern. Most of the food safety analytical and detection methods are expensive, labor intensive, and time consuming. A safe, rapid, reliable, and nondestructive detection method is needed to assure consumers that food products are safe to consume. Terahertz (THz) radiation, which has properties of both microwave and infrared, can penetrate and interact with many commonly used materials. Owing to the technological developments in sources and detectors, THz spectroscopic imaging has transitioned from a laboratory-scale technique into a versatile imaging tool with many practical applications. In recent years, THz imaging has been shown to have great potential as an emerging nondestructive tool for food inspection. THz spectroscopy provides qualitative and quantitative information about food samples. The main applications of THz in food industries include detection of moisture, foreign bodies, inspection, and quality control. Other applications of THz technology in the food industry include detection of harmful compounds, antibiotics, and microorganisms. THz spectroscopy is a great tool for characterization of carbohydrates, amino acids, fatty acids, and vitamins. Despite its potential applications, THz technology has some limitations, such as limited penetration, scattering effect, limited sensitivity, and low limit of detection. THz technology is still expensive, and there is no available THz database library for food compounds. The scanning speed needs to be improved in the future generations of THz systems. Although many technological aspects need to be improved, THz technology has already been established in the food industry as a powerful tool with great detection and quantification ability. -
VIIRS) Sensor Data Record (SDR) User's Guide (Version 1.2
NOAA Technical Report NESDIS 142 Visible Infrared Imaging Radiometer Suite (VIIRS) Sensor Data Record (SDR) User’s Guide Version 1.2 Washington, D.C. 10 September 2013 U.S. DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration National Environmental Satellite, Data, and Information Service NOAA TECHNICAL REPORTS National Environmental Satellite, Data, and Information Service The National Environmental Satellite, Data, and Information Service (NESDIS) manages the Nation’s civilian Earth-observing satellite systems, as well as global national data bases for meteorology, oceanography, geophysics, and solar-terrestrial sciences. From these sources, it develops and disseminates environmental data and information products critical to the protection of life and property, national defense, the national economy, energy development and distribution, global food supplies, and the development of natural resources. Publication in the NOAA Technical Report series does not preclude later publication in scientific journals in expanded or modified form. The NESDIS series of NOAA Technical Reports is a continuation of the former NESS and EDIS series of NOAA Technical Reports and the NESC and EDS series of Environmental Science Services Administration (ESSA) Technical Reports. An electronic copy of this report may be obtained at: https://cs.star.nesdis.noaa.gov/NCC/VIIRS A limited number of copies of earlier reports are available by contacting, NOAA/NESDIS/STAR, 5830 University Research Ct, Suite 2600, College Park, Maryland 20740, Phone: 301 683-3490. A partial listing of more recent reports appears below: NESDIS 111 An Algorithm for Correction of Lunar Contamination in AMSU-A Data. Seiichiro Kigawa and Tsan Mo, December 2002. NESDIS 112 Sampling Errors of the Global Mean Sea Level Derived from TOPEX/Poseidon Altimetry. -
Arxiv:1512.01105V1 [Astro-Ph.GA] 3 Dec 2015
Accepted to the Astrophysical Journal on November 30, 2015 A Preprint typeset using LTEX style emulateapj v. 5/2/11 THE CHANDRA COSMOS LEGACY SURVEY: OPTICAL/IR IDENTIFICATIONS S. Marchesi1,2,3, F. Civano1,2, M. Elvis2, M. Salvato4, M. Brusa3,5, A. Comastri5, R. Gilli5, G. Hasinger6, G. Lanzuisi3,5, T. Miyaji7,8, E. Treister9, C.M. Urry1, C. Vignali3,5, G. Zamorani5, V. Allevato10, N. Cappelluti5, C. Cardamone11, A. Finoguenov10, R. E. Griffiths12, A. Karim13, C. Laigle14, S. M. LaMassa1, K. Jahnke15, P. Ranalli16, K. Schawinski17, E. Schinnerer18,19, J. D. Silverman20, V. Smolcic21, H. Suh6,2, B. Trakhtenbrot17 Accepted to the Astrophysical Journal on November 30, 2015 ABSTRACT We present the catalog of optical and infrared counterparts of the Chandra COSMOS-Legacy Survey, a 4.6 Ms Chandra program on the 2.2 deg2 of the COSMOS field, combination of 56 new overlapping observations obtained in Cycle 14 with the previous C-COSMOS survey. In this Paper we report the i, K, and 3.6 µm identifications of the 2273 X-ray point sources detected in the new Cycle 14 observations. We use the likelihood ratio technique to derive the association of optical/infrared (IR) counterparts for 97% of the X-ray sources. We also update the information for the 1743 sources detected in C-COSMOS, using new K and 3.6 µm information not available when the C-COSMOS analysis was performed. The final catalog contains 4016 X-ray sources, 97% of which have an op- tical/IR counterpart and a photometric redshift, while ≃54% of the sources have a spectroscopic redshift. -
X-Ray Properties of Young Stars and Stellar Clusters 313
Feigelson et al.: X-Ray Properties of Young Stars and Stellar Clusters 313 X-Ray Properties of Young Stars and Stellar Clusters Eric Feigelson and Leisa Townsley Pennsylvania State University Manuel Güdel Paul Scherrer Institute Keivan Stassun Vanderbilt University Although the environments of star and planet formation are thermodynamically cold, sub- stantial X-ray emission from 10–100 MK plasmas is present. In low-mass pre-main-sequence stars, X-rays are produced by violent magnetic reconnection flares. In high-mass O stars, they are produced by wind shocks on both stellar and parsec scales. The recent Chandra Orion Ultra- deep Project, XMM-Newton Extended Survey of Taurus, and Chandra studies of more distant high-mass star-forming regions reveal a wealth of X-ray phenomenology and astrophysics. X- ray flares mostly resemble solar-like magnetic activity from multipolar surface fields, although extreme flares may arise in field lines extending to the protoplanetary disk. Accretion plays a secondary role. Fluorescent iron line emission and absorption in inclined disks demonstrate that X-rays can efficiently illuminate disk material. The consequent ionization of disk gas and irradiation of disk solids addresses a variety of important astrophysical issues of disk dynam- ics, planet formation, and meteoritics. New observations of massive star-forming environments such as M 17, the Carina Nebula, and 30 Doradus show remarkably complex X-ray morpholo- gies including the low-mass stellar population, diffuse X-ray flows from blister HII regions, and inhomogeneous superbubbles. X-ray astronomy is thus providing qualitatively new insights into star and planet formation. 1. INTRODUCTION ment of the stellar surface by electron beams. -
Color Centers in Additively Colored Csbr David W
Physics and Astronomy Publications Physics and Astronomy 9-1962 Color Centers in Additively Colored CsBr David W. Lynch Iowa State University, [email protected] Follow this and additional works at: http://lib.dr.iastate.edu/physastro_pubs Part of the Atomic, Molecular and Optical Physics Commons, and the Optics Commons The ompc lete bibliographic information for this item can be found at http://lib.dr.iastate.edu/physastro_pubs/8. For information on how to cite this item, please visit http://lib.dr.iastate.edu/howtocite.html. This Article is brought to you for free and open access by the Physics and Astronomy at Iowa State University Digital Repository. It has been accepted for inclusion in Physics and Astronomy Publications by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Color Centers in Additively Colored CsBr Abstract Color centers have been studied in CsBr single crystals additively colored with potassium or cesium. More than ten absorption bands were produced, most of which had previously been found in crystals colored by ionizing radiation. All bands produced by irradiation at or above liquid nitrogen temperature appear to arise from trapped electrons. The most prominent bands in the additively colored crystals are the F band at 642 mμ (liquid nitrogen temperature) and a band at 243 mμ which appears to be due to an impurity. Optically bleaching the F band at 200°K produces bands analogous to the M and R bands in other alkali halides while bleaching at liquid nitrogen temperature yields a broad band identified as the F′ band. -
Living & Ulvac
LIVING & ULVAC Communication Infrastructure Front Line for Diffusion of Cellular Phones Further acceleration via Development of High-performance Microwave Communication Devices Reporting from Toshiba Corporation Social Infrastructure Systems Company Microwave Solid-State Engineering Department, Komukai Complex Application field of Microwave SATCOM/VSAT Marine Radar Weather Radar Fixed Wireless Access Digital Broadcasting TTL FPU Fixed Wireless Access SNG FPU STL TSL WiMAX Fixed Wireless Access Industrial-Use Mobile Phone Data from Toshiba Corporation Social Infrastructure Systems Company VSAT: Very Small Aperture Terminal STL: Studio to Transmitter Link SATCOM: Satellite Communication TSL: Transmitter to Studio Link WiMAX: Worldwide Interoperability for Microwave Access FPU: Field Pickup Unit SNG: Satellite News Gathering ITS: Intelligent Transport Systems TTL: Transmitter to Transmitter Link LIVING & ULVAC 10 ULVAC | No.64 More than 1.75 billion cellular phones are manufactured annually worldwide (2012 survey by Gartner, Inc.), and 94.5% of households in Japan have one or more cellular phones (2012 survey by the Ministry of Internal Affairs and Communications). In particular, it would be no‥exaggeration‥to‥say‥that‥almost‥everyone‥in‥their‥twenties‥and‥almost‥all‥university‥students‥have‥a‥cellular‥phone.‥In‥addition,‥it‥may‥ be safely said that today, a cellular phone is also a must-have item for elderly people. Originally, wireless communication was achieved with wireless communication equipment that made use of short wave radio frequencies to connect two parties directly. Wireless com- Communication Infrastructure Front Line munication via cellular phones is significantly different from wireless communication of the past in that cellular phones connect two com- for Diffusion of Cellular Phones municating parties via communication stations, which are connected via a wired communication network.