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Bibliografias temáticas / Laser communication systems

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Literatura científica selecionada sobre o tema "Laser communication systems"

Autor: Grafiati

Publicado: 4 de junho de 2021

Última modificação: 5 de março de 2023

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Artigos de revistas sobre o assunto "Laser communication systems"

1

Ke, Qiang. "Numerical Simulation of Chaotic Laser Secure Communication". Advanced Materials Research 798-799 (setembro de 2013): 570–73. http://dx.doi.org/10.4028/www.scientific.net/amr.798-799.570.

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Using the idea of drive-response synchronization, we discuss the principle, numerical simulation of chaotic laser communication. Compared to traditional communications systems, the chaotic laser communication system has a well-kept secret performance, but the chaos synchronization requirements are very strict.

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2

Pengyuan Chang, Pengyuan Chang, Tiantian Shi Tiantian Shi, Shengnan Zhang Shengnan Zhang, Haosen Shang Haosen Shang, Duo Pan Duo Pan e Jingbiao Chen Jingbiao Chen. "Faraday laser at Rb 1529 nm transition for optical communication systems". Chinese Optics Letters 15, n.º 12 (2017): 121401. http://dx.doi.org/10.3788/col201715.121401.

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3

Zeng Fengjiao, 曾凤娇, 杨康建 Yang Kangjian, 晏旭 Yan Xu, 赵孟孟 Zhao Mengmeng, 杨平 Yang Ping e 文良华 Wen Lianghua. "Research Progress on Underwater Laser Communication Systems". Laser & Optoelectronics Progress 58, n.º 3 (2021): 0300002–30000226. http://dx.doi.org/10.3788/lop202158.0300002.

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4

Cai, Chengkun, e Jian Wang. "Femtosecond Laser-Fabricated Photonic Chips for Optical Communications: A Review". Micromachines 13, n.º 4 (16 de abril de 2022): 630. http://dx.doi.org/10.3390/mi13040630.

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Integrated optics, having the unique properties of small size, low loss, high integration, and high scalability, is attracting considerable attention and has found many applications in optical communications, fulfilling the requirements for the ever-growing information rate and complexity in modern optical communication systems. Femtosecond laser fabrication is an acknowledged technique for producing integrated photonic devices with unique features, such as three-dimensional fabrication geometry, rapid prototyping, and single-step fabrication. Thus, plenty of femtosecond laser-fabricated on-chip devices have been manufactured to realize various optical communication functions, such as laser generation, laser amplification, laser modulation, frequency conversion, multi-dimensional multiplexing, and photonic wire bonding. In this paper, we review some of the most relevant research progress in femtosecond laser-fabricated photonic chips for optical communications, which may break new ground in this area. First, the basic principle of femtosecond laser fabrication and different types of laser-inscribed waveguides are briefly introduced. The devices are organized into two categories: active devices and passive devices. In the former category, waveguide lasers, amplifiers, electric-optic modulators, and frequency converters are reviewed, while in the latter, polarization multiplexers, mode multiplexers, and fan-in/fan-out devices are discussed. Later, photonic wire bonding is also introduced. Finally, conclusions and prospects in this field are also discussed.

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5

Strakhov, S. Yu, A. V. Trilis e N. V. Sotnikova. "Specifics of transmitting telescopes for laser communication systems". Journal of Optical Technology 88, n.º 5 (1 de maio de 2021): 264. http://dx.doi.org/10.1364/jot.88.000264.

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6

Giuliano, Giovanni, Leslie Laycock, Duncan Rowe e Anthony E. Kelly. "Solar rejection in laser based underwater communication systems". Optics Express 25, n.º 26 (20 de dezembro de 2017): 33066. http://dx.doi.org/10.1364/oe.25.033066.

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7

Moatlhodi, Ogomoditse O., Nonofo M. J. Ditshego e Ravi Samikannu. "Vertical Cavity Surface Emitting Lasers as Sources for Optical Communication Systems: A Review". Journal of Nano Research 65 (dezembro de 2020): 51–96. http://dx.doi.org/10.4028/www.scientific.net/jnanor.65.51.

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Next generation integrated photonic circuits will be dominated by small footprint devices with lower power consumption, low threshold currentsand high efficiencies. Vertical Cavity Surface Emitting Lasers (VCSELs) having those attractive qualities has shown results to meet the next generation demands for optical communication sources. VCSELs applications are sensors, data com, optical communication, spectroscopy, printers, optical storage, laser displays, atomic optical clocks, laser radar, optical signal processing to name a few. This review centres around on the basic operation of semiconductor lasers, structure analysis of the devices and parameter optimisation for optical communication systems. This paper will provide comparisons on growth techniques and material selection and intends to give the best material realisation for nano optical sources that are up to date as used in optical communication systems. It also provides summarised improvements by other research groups in realisation of VCSELs looking at speeds, efficiency, temperature dependence and the device physical dimensions. Different semiconductor device growth methods, light emitting materials and VCSELs state of art are reviewed. Discussions and a comparisons on different methods used for realising VCSELs are also looked into in this paper.

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8

Niu, Shen, Yue Song, Ligong Zhang, Yongyi Chen, Lei Liang, Ye Wang, Li Qin et al. "Research Progress of Monolithic Integrated DFB Laser Arrays for Optical Communication". Crystals 12, n.º 7 (21 de julho de 2022): 1006. http://dx.doi.org/10.3390/cryst12071006.

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Photonic integrated circuits (PICs) play a leading role in modern information and communications technology. Among the core devices in PICs is the distributed feedback (DFB) multi-wavelength semiconductor laser array. Multi-wavelength semiconductor laser arrays can be integrated on a single chip and have the advantages of high stability, good single-mode performance, and narrow line width. The wavelength tuning range has been expanded through the design of the DFB laser array, which is an ideal light source for wavelength-division multiplexing systems. The preparation of DFB laser arrays with a large number of channels, ease of mass production, and accurate emission wavelengths has become an important field of research. The connection methods of lasers in DFB laser arrays are introduced systematically and the current methods of manufacturing multi-wavelength DFB laser arrays covering the perspective of technical principles, technical advantages and disadvantages, main research progress, and research status are summarized.

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Dmytryszyn, Mark, Matthew Crook e Timothy Sands. "Preparing for Satellite Laser Uplinks and Downlinks". Sci 2, n.º 1 (18 de março de 2020): 16. http://dx.doi.org/10.3390/sci2010016.

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The use of Light Amplification by Stimulated Emission of Radiation (i.e., LASERs or lasers) by the U.S. Department of Defense is not new and includes laser weapons guidance, laser-aided measurements, even lasers as weapons (e.g., Airborne Laser). Lasers in support of telecommunications is also not new. The use of laser light in fiber optics shattered thoughts on communications bandwidth and throughput. Even the use of lasers in space is no longer new. Lasers are being used for satellite-to-satellite crosslinking. Laser communication can transmit orders-of-magnitude more data using orders-of-magnitude less power and can do so with minimal risk of exposure to the sending and receiving terminals. What is new is using lasers as the uplink and downlink between the terrestrial segment and the space segment of satellite systems. More so, the use of lasers to transmit and receive data between moving terrestrial segments (e.g., ships at sea, airplanes in flight) and geosynchronous satellites is burgeoning. This manuscript examines the technological maturation of employing lasers as the signal carrier for satellite communications linking terrestrial and space systems. The purpose of the manuscript is to develop key performance parameters (KPPs) to inform U.S. Department of Defense initial capabilities documents (ICDs) for near-future satellite acquisition and development. By appreciating the history and technological challenges of employing lasers rather than traditional radio frequency sources for satellite uplink and downlink signal carriers, this manuscript recommends ways for the U.S. Department of Defense to employ lasers to transmit and receive high bandwidth, large-throughput data from moving platforms that need to retain low probabilities of detection, intercept, and exploitation (e.g., carrier battle group transiting to a hostile area of operations, unmanned aerial vehicle collecting over adversary areas). The manuscript also intends to identify commercial sector early-adopter fields and those fields likely to adapt to laser employment for transmission and receipt.

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10

Laksono, Pranoto Budi. "A STUDY OF THE INFLUENCE OF 650 nm LASER INTERFERENCE ON VISIBLE LASER LIGHT COMMUNICATION SYSTEM". TEKNOKOM 4, n.º 2 (1 de setembro de 2021): 60–65. http://dx.doi.org/10.31943/teknokom.v4i2.66.

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Visible Laser Light Communication System (VLLC) is a wireless communication system, using laser as the medium. In the data transfer process, it is possible to have optical interference where 2 laser beams coincide with one point on the reflector. Research on the effect of laser source interference has been carried out by several researchers including mitigation actions to reduce its effects. This experiment uses 2 optical distance sensors that produce a laser with a wavelength of 650 nm with a power <=4.1 mW and with the direction of the laser beam both of them cross each other. To determine the effect of the interference of two laser beams when crossing the communication process in the visible light communication system, a reflector is used which can capture the two laser beams and the reflector can be shifted gradually so that a condition can be obtained where the two laser beams meet at one point. From the measurements made at the points after the laser beam crossing, the measurements at the point where the beam crossed, and the measurements at the points before the beam crossing, it was obtained data, at the exact point where the laser beam crossed the interference occurred, which is indicated by unstable output voltage of the two lasers, so that communication at the point of intersection is disrupted. However, if outside the point of contact both before and after the point of contact, interference and communication systems will not occur.

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Teses / dissertações sobre o assunto "Laser communication systems"

1

Sabala, Ryan J. "Satellite Attitude Determination Using Laser Communication Systems". Ohio University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1218636153.

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2

Sofka, Jozef. "New generation of gimbals systems for aerospace applications". Diss., Online access via UMI:, 2007.

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3

Qureshi, Zihad. "Vertical cavity surface emitting lasers in high speed optical data communications". Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608126.

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4

Bar, Siman Tov Omar. "Adaptive optimization of a free-space laser communication system under dynamic link attenuation". Diss., Online access via UMI:, 2009.

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Thesis (M.S.)--State University of New York at Binghamton, Thomas J. Watson School of Engineering and Applied Science, Department of Electrical and Computer Engineering, 2009.
Includes bibliographical references.

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5

Bonk, Scott S. "The use of point-to-point lasers for navy ships". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Jun%5FBonk.pdf.

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6

Timus, Oguzhan. "Free space optic communication for Navy surface ship platforms". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Mar%5FTimus.pdf.

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7

Zhu, Benyuan. "Multichannel grating cavity laser for optically multiplexed communication systems". Thesis, University of Bath, 1996. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320438.

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8

Lee, Myron S. M. Massachusetts Institute of Technology. "Optomechanical and wavelength alignments of CubeSat laser communication Systems". Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/112470.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 97-100).
While the introduction of CubeSats has enabled the scientific, commercial, and governmental communities to launch space missions more quickly at lower costs, the communication subsystems of the platform are limited by a heavily regulated and overcrowded RF spectrum. Scientific instruments with increasing capabilities on CubeSats are generating massive amounts of data and are quickly pushing the boundaries of the data rates of current RF communication systems. An alternative to the traditional RF communication system is the free space optical (FSO) communication system. With higher power efficiency, FSO communication, or lasercom, can potentially provide higher data rates using less power and also avoid the RF spectrum regulatory process. MIT's Nanosatellite Optical Downlink Experiment (NODE) is an effort to demonstrate low cost and high speed optical downlink from LEO for CubeSats, and this thesis focuses on alignments in the optomechanical system and transmitter system of the NODE payload. First, simulation and analyses are performed on an optomechanical model of NODE to study the effects potential misalignments of hardware components can have on the overall system. Second, we present an autonomous optimization algorithm that monitors the conditions of the transmitter system and compensates for wavelength misalignments between the transmitter optical components caused by variations in the thermal environment.
by Myron Lee.
S.M.

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9

Johnson, Peter Thomas. "Spectral correlation of semiconductor laser". Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385428.

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10

Hill, Timothy J. "Interference of intensity noise in a multimode Nd:YAG laser". Title page, abstract and contents only, 2003. http://web4.library.adelaide.edu.au/theses/09PH/09phh6484.pdf.

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Includes bibliographical references (leaves 151-163). Investigates the behaviour of the intensity noise in a multimode Nd:YAG laser. The collective modes of oscillation are excited by broadband ambient noise. Because the phase of the excitation is unknown, a cross spectral technique to measure the antiphase dynamics directly and form a picture of the intensity noise interference for two to five mode operation is developed. For three mode operation, the contributions of the longitudinal modes to collective modes is measured.

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Mais fontes

Livros sobre o assunto "Laser communication systems"

1

1923-, Katzman Morris, ed. Laser satellite communications. Englewood Cliffs, NJ: Prentice-Hall, 1987.

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2

Coherent lightwave communication systems. Boston: Artech House, 1995.

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3

L, Casey William, ed. Laser communications in space. Boston: Artech House, 1995.

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4

J, Adams M., e Institution of Electrical Engineers, eds. Semiconductor lasers for long-wavelength optical-fibre communications systems. London, U.K: P. Peregrinus on behalf of the Institution of Electrical Engineers, 1987.

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5

Introduction to lightwave communication systems. Boston: Artech House, 1997.

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6

1959-, Voelz David George, Ricklin Jennifer Crider 1960- e Society of Photo-optical Instrumentation Engineers., eds. Free-space laser communication and laser imaging: 30-31 July, 2001, San Diego, [Calif.]. Bellingham, Wash: SPIE, 2001.

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7

1959-, Voelz David George, Ricklin Jennifer Crider 1960- e Society of Photo-optical Instrumentation Engineers., eds. Free-space laser communication and laser imaging II: 9-11 July, 2002, Seattle, Washington. Bellingham, Wash: SPIE, 2002.

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8

C, Ricklin Jennifer, Voelz David G e Society of Photo-optical Instrumentation Engineers., eds. Free-space laser communication and laser imaging: 30-31 July, 2001, San Diego, California. Bellingham, Wash., USA: SPIE, 2002.

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9

E, Enstrom R., Longeway P. A e Langley Research Center, eds. Monolithic narrow-linewidth InGaAsP semiconductor laser for coherent optical communications. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1989.

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10

E, Enstrom R., Longeway P. A e Langley Research Center, eds. Monolithic narrow-linewidth InGaAsP semiconductor laser for coherent optical communications. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1989.

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Capítulos de livros sobre o assunto "Laser communication systems"

1

Klotzkin, David J. "Laser Communication Systems I: Amplitude Modulated Systems". In Introduction to Semiconductor Lasers for Optical Communications, 293–321. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-24501-6_11.

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2

Al-Ramli, F. K. "Optimum Receiver Structure and Filter Design for MPAM Optical Space Communication Systems". In Laser in der Technik / Laser in Engineering, 192–95. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-84736-3_35.

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3

Raj, Utkarsh, Neha Nidhi e Vijay Nath. "Automated Toll Plaza Using Barcode-Laser Scanning Technology". In Nanoelectronics, Circuits and Communication Systems, 475–81. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-0776-8_44.

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4

Majumdar, Arun K. "Laser Satellite Communications: Fundamentals, Systems, Technologies, and Applications". In Laser Communication with Constellation Satellites, UAVs, HAPs and Balloons, 63–95. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-03972-0_3.

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5

Watanabe, Kota, Takuto Koyama, Hiroshi Koga, Kiyotaka Izumi e Takeshi Tsujimura. "Tactical Alignment of Aerial Transmission Laser Beam for Free Space Optics Communication". In Lecture Notes in Networks and Systems, 102–14. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-14314-4_10.

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6

Jono, Shun, Takuto Koyama, Kota Watanabe, Kiyotaka Izumi e Takeshi Tsujimura. "Optical Simulations on Aerial Transmitting Laser Beam for Free Space Optics Communication". In Advances in Networked-Based Information Systems, 59–70. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-84913-9_6.

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7

Majumdar, Arun K. "Laser-Based Satellite and Inter-satellite Communication Systems: Advanced Technologies and Performance Analysis". In Laser Communication with Constellation Satellites, UAVs, HAPs and Balloons, 199–229. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-03972-0_7.

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8

Majumdar, Arun K. "Optical Laser Links in Space-Based Systems for Global Communications Network Architecture: Space/Aerial, Terrestrial, and Underwater Platforms". In Laser Communication with Constellation Satellites, UAVs, HAPs and Balloons, 97–128. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-03972-0_4.

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9

Dudin, Alexander N., Valentina I. Klimenok e Vladimir M. Vishnevsky. "Mathematical Models and Methods of Investigation of Hybrid Communication Networks Based on Laser and Radio Technologies". In The Theory of Queuing Systems with Correlated Flows, 241–306. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-32072-0_5.

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Klotzkin, David J. "Coherent Communication Systems". In Introduction to Semiconductor Lasers for Optical Communications, 323–54. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-24501-6_12.

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Trabalhos de conferências sobre o assunto "Laser communication systems"

1

Giuliano, Giovanni, Shaun Viola, Scott Watson, Leslie Laycock, Duncan Rowe e Anthony E. Kelly. "Laser based underwater communication systems". In 2016 18th International Conference on Transparent Optical Networks (ICTON). IEEE, 2016. http://dx.doi.org/10.1109/icton.2016.7550382.

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2

Hamilton, S. A., R. S. Bondurant, D. M. Boroson, J. W. Burnside, D. O. Caplan, E. A. Dauler, A. S. Fletcher et al. "Long-Haul Atmospheric Laser Communication Systems§". In Optical Fiber Communication Conference. Washington, D.C.: OSA, 2011. http://dx.doi.org/10.1364/ofc.2011.owx2.

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3

Garaymovich, Nicolay P., Vladimir N. Grigoriev, Alexander P. Huppenen, Michael A. Sadovnikov, Victor D. Shargorodsky e Victor V. Sumerin. "Free-space laser communication systems: internationally and in Russia". In Laser Optics 2000, editado por Serguei A. Gurevich e Nikolay N. Rosanov. SPIE, 2001. http://dx.doi.org/10.1117/12.418827.

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4

Roberts, Lewis C. "Satellite Laser Communication and Adaptive Optics". In Adaptive Optics: Analysis, Methods & Systems. Washington, D.C.: OSA, 2020. http://dx.doi.org/10.1364/aoms.2020.jw4g.1.

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5

Chen, Yan, e Tianzhi Yao. "Laser Communication Theorem and New Communication Engineering Revolution". In ICAIIS 2021: 2021 2nd International Conference on Artificial Intelligence and Information Systems. New York, NY, USA: ACM, 2021. http://dx.doi.org/10.1145/3469213.3471323.

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6

Hacker, G. "Homodyne Detection for Optical Space Communications". In Coherent Laser Radar. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/clr.1987.thb1.

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Optical communication systems offer significant advantages over conventional microwave communications. They have the potential to provide high rate data links between satellites. Moving on to the optical frequency regime provides increased antenna gain with small congestion occuring in microwave communications. These properties and the high privacy due to the high directivity and small beam width make optical communications systems an ideal candidate for future intersatellite/interorbit data links.

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7

Bagrov, Alexander V., e Vladimir P. Lukin. "Laser optical communication systems with space transmitters". In SPIE Proceedings, editado por Gelii A. Zherebtsov e Gennadii G. Matvienko. SPIE, 2006. http://dx.doi.org/10.1117/12.675242.

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8

Shubert, Paul D. "Atmospheric fade probability in moderate aperture laser communication systems". In Free-Space Laser Communications XXXI, editado por Hamid Hemmati e Don M. Boroson. SPIE, 2019. http://dx.doi.org/10.1117/12.2508069.

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9

Christopher, Paul. "Climate Satellites with Laser Communication Links". In 28th AIAA International Communications Satellite Systems Conference (ICSSC-2010). Reston, Virigina: American Institute of Aeronautics and Astronautics, 2010. http://dx.doi.org/10.2514/6.2010-8849.

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10

Carlson, N. W., G. A. Evans, D. P. Bour e S. K. Liew. "Applications of surface-emitting lasers to coherent communication systems". In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/oam.1990.tul6.

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Monolithic, surface-emitting laser array technology is an attractive approach for producing the high-power coherent sources required for free-space coherent optical communications. Recent developments will be reviewed, and conceptual array designs for communication systems will be described.

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Relatórios de organizações sobre o assunto "Laser communication systems"

1

Ruggiero, A., e A. Orgren. Development of Operational Free-Space-Optical (FSO) Laser Communication Systems Final Report CRADA No. TC02093.0. Office of Scientific and Technical Information (OSTI), agosto de 2017. http://dx.doi.org/10.2172/1389996.

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2

Gibson, Steve, e Tsu-Chin Tsao. Control, Filtering and System Identification for High Energy Lasers and Laser Communications. Fort Belvoir, VA: Defense Technical Information Center, janeiro de 2012. http://dx.doi.org/10.21236/ada565747.

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3

Wilkins, Gary D. Eye-Safe 2-Micron Laser Communications System. Fort Belvoir, VA: Defense Technical Information Center, janeiro de 1996. http://dx.doi.org/10.21236/ada309907.

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4

Taylor, Johnny A., Allen D. Pillsbury e Don M. Boroson. Space Qualification for an Intersatellite Laser Communications System. Fort Belvoir, VA: Defense Technical Information Center, março de 1993. http://dx.doi.org/10.21236/ada265145.

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5

Wilkins, Gary D. Atmospheric Transverse Coherence Length Measurement System for Laser Communications. Fort Belvoir, VA: Defense Technical Information Center, fevereiro de 1993. http://dx.doi.org/10.21236/ada263563.

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6

Bourrier, Mathilde, Michael Deml e Farnaz Mahdavian. Comparative report of the COVID-19 Pandemic Responses in Norway, Sweden, Germany, Switzerland and the United Kingdom. University of Stavanger, novembro de 2022. http://dx.doi.org/10.31265/usps.254.

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The purpose of this report is to compare the risk communication strategies and public health mitigation measures implemented by Germany, Norway, Sweden, Switzerland, and the United Kingdom (UK) in 2020 in response to the COVID-19 pandemic based on publicly available documents. The report compares the country responses both in relation to one another and to the recommendations and guidance of the World Health Organization where available. The comparative report is an output of Work Package 1 from the research project PAN-FIGHT (Fighting pandemics with enhanced risk communication: Messages, compliance and vulnerability during the COVID-19 outbreak), which is financially supported by the Norwegian Research Council's extraordinary programme for corona research. PAN-FIGHT adopts a comparative approach which follows a “most different systems” variation as a logic of comparison guiding the research (Przeworski & Teune, 1970). The countries in this study include two EU member States (Sweden, Germany), one which was engaged in an exit process from the EU membership (the UK), and two non-European Union states, but both members of the European Free Trade Association (EFTA): Norway and Switzerland. Furthermore, Germany and Switzerland govern by the Continental European Federal administrative model, with a relatively weak central bureaucracy and strong subnational, decentralised institutions. Norway and Sweden adhere to the Scandinavian model—a unitary but fairly decentralised system with power bestowed to the local authorities. The United Kingdom applies the Anglo-Saxon model, characterized by New Public Management (NPM) and decentralised managerial practices (Einhorn & Logue, 2003; Kuhlmann & Wollmann, 2014; Petridou et al., 2019). In total, PAN-FIGHT is comprised of 5 Work Packages (WPs), which are research-, recommendation-, and practice-oriented. The WPs seek to respond to the following research questions and accomplish the following: WP1: What are the characteristics of governmental and public health authorities’ risk communication strategies in five European countries, both in comparison to each other and in relation to the official strategies proposed by WHO? WP2: To what extent and how does the general public’s understanding, induced by national risk communication, vary across five countries, in relation to factors such as social capital, age, gender, socio-economic status and household composition? WP3: Based on data generated in WP1 and WP2, what is the significance of being male or female in terms of individual susceptibility to risk communication and subsequent vulnerability during the COVID-19 outbreak? WP4: Based on insight and knowledge generated in WPs 1 and 2, what recommendations can we offer national and local governments and health institutions on enhancing their risk communication strategies to curb pandemic outbreaks? WP5: Enhance health risk communication strategies across five European countries based upon the knowledge and recommendations generated by WPs 1-4. Pre-pandemic preparedness characteristics All five countries had pandemic plans developed prior to 2020, which generally were specific to influenza pandemics but not to coronaviruses. All plans had been updated following the H1N1 pandemic (2009-2010). During the SARS (2003) and MERS (2012) outbreaks, both of which are coronaviruses, all five countries experienced few cases, with notably smaller impacts than the H1N1 epidemic (2009-2010). The UK had conducted several exercises (Exercise Cygnet in 2016, Exercise Cygnus in 2016, and Exercise Iris in 2018) to check their preparedness plans; the reports from these exercises concluded that there were gaps in preparedness for epidemic outbreaks. Germany also simulated an influenza pandemic exercise in 2007 called LÜKEX 07, to train cross-state and cross-department crisis management (Bundesanstalt Technisches Hilfswerk, 2007). In 2017 within the context of the G20, Germany ran a health emergency simulation exercise with WHO and World Bank representatives to prepare for potential future pandemics (Federal Ministry of Health et al., 2017). Prior to COVID-19, only the UK had expert groups, notably the Scientific Advisory Group for Emergencies (SAGE), that was tasked with providing advice during emergencies. It had been used in previous emergency events (not exclusively limited to health). In contrast, none of the other countries had a similar expert advisory group in place prior to the pandemic. COVID-19 waves in 2020 All five countries experienced two waves of infection in 2020. The first wave occurred during the first half of the year and peaked after March 2020. The second wave arrived during the final quarter. Norway consistently had the lowest number of SARS-CoV-2 infections per million. Germany’s counts were neither the lowest nor the highest. Sweden, Switzerland and the UK alternated in having the highest numbers per million throughout 2020. Implementation of measures to control the spread of infection In Germany, Switzerland and the UK, health policy is the responsibility of regional states, (Länders, cantons and nations, respectively). However, there was a strong initial centralized response in all five countries to mitigate the spread of infection. Later on, country responses varied in the degree to which they were centralized or decentralized. Risk communication In all countries, a large variety of communication channels were used (press briefings, websites, social media, interviews). Digital communication channels were used extensively. Artificial intelligence was used, for example chatbots and decision support systems. Dashboards were used to provide access to and communicate data.

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Chapman, Ray, Phu Luong, Sung-Chan Kim e Earl Hayter. Development of three-dimensional wetting and drying algorithm for the Geophysical Scale Transport Multi-Block Hydrodynamic Sediment and Water Quality Transport Modeling System (GSMB). Engineer Research and Development Center (U.S.), julho de 2021. http://dx.doi.org/10.21079/11681/41085.

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The Environmental Laboratory (EL) and the Coastal and Hydraulics Laboratory (CHL) have jointly completed a number of large-scale hydrodynamic, sediment and water quality transport studies. EL and CHL have successfully executed these studies utilizing the Geophysical Scale Transport Modeling System (GSMB). The model framework of GSMB is composed of multiple process models as shown in Figure 1. Figure 1 shows that the United States Army Corps of Engineers (USACE) accepted wave, hydrodynamic, sediment and water quality transport models are directly and indirectly linked within the GSMB framework. The components of GSMB are the two-dimensional (2D) deep-water wave action model (WAM) (Komen et al. 1994, Jensen et al. 2012), data from meteorological model (MET) (e.g., Saha et al. 2010 - http://journals.ametsoc.org/doi/pdf/10.1175/2010BAMS3001.1), shallow water wave models (STWAVE) (Smith et al. 1999), Coastal Modeling System wave (CMS-WAVE) (Lin et al. 2008), the large-scale, unstructured two-dimensional Advanced Circulation (2D ADCIRC) hydrodynamic model (http://www.adcirc.org), and the regional scale models, Curvilinear Hydrodynamics in three dimensions-Multi-Block (CH3D-MB) (Luong and Chapman 2009), which is the multi-block (MB) version of Curvilinear Hydrodynamics in three-dimensions-Waterways Experiments Station (CH3D-WES) (Chapman et al. 1996, Chapman et al. 2009), MB CH3D-SEDZLJ sediment transport model (Hayter et al. 2012), and CE-QUAL Management - ICM water quality model (Bunch et al. 2003, Cerco and Cole 1994). Task 1 of the DOER project, “Modeling Transport in Wetting/Drying and Vegetated Regions,” is to implement and test three-dimensional (3D) wetting and drying (W/D) within GSMB. This technical note describes the methods and results of Task 1. The original W/D routines were restricted to a single vertical layer or depth-averaged simulations. In order to retain the required 3D or multi-layer capability of MB-CH3D, a multi-block version with variable block layers was developed (Chapman and Luong 2009). This approach requires a combination of grid decomposition, MB, and Message Passing Interface (MPI) communication (Snir et al. 1998). The MB single layer W/D has demonstrated itself as an effective tool in hyper-tide environments, such as Cook Inlet, Alaska (Hayter et al. 2012). The code modifications, implementation, and testing of a fully 3D W/D are described in the following sections of this technical note.

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Atkinson, Dan, e Alex Hale, eds. From Source to Sea: ScARF Marine and Maritime Panel Report. Society of Antiquaries of Scotland, setembro de 2012. http://dx.doi.org/10.9750/scarf.09.2012.126.

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The main recommendations of the panel report can be summarised under four headings: 1. From Source to Sea: River systems, from their source to the sea and beyond, should form the focus for research projects, allowing the integration of all archaeological work carried out along their course. Future research should take a holistic view of the marine and maritime historic environment, from inland lakes that feed freshwater river routes, to tidal estuaries and out to the open sea. This view of the landscape/seascape encompasses a very broad range of archaeology and enables connections to be made without the restrictions of geographical or political boundaries. Research strategies, programmes From Source to Sea: ScARF Marine and Maritime Panel Report iii and projects can adopt this approach at multiple levels; from national to site-specific, with the aim of remaining holistic and cross-cutting. 2. Submerged Landscapes: The rising research profile of submerged landscapes has recently been embodied into a European Cooperation in Science and Technology (COST) Action; Submerged Prehistoric Archaeology and Landscapes of the Continental Shelf (SPLASHCOS), with exciting proposals for future research. Future work needs to be integrated with wider initiatives such as this on an international scale. Recent projects have begun to demonstrate the research potential for submerged landscapes in and beyond Scotland, as well as the need to collaborate with industrial partners, in order that commercially-created datasets can be accessed and used. More data is required in order to fully model the changing coastline around Scotland and develop predictive models of site survival. Such work is crucial to understanding life in early prehistoric Scotland, and how the earliest communities responded to a changing environment. 3. Marine & Maritime Historic Landscapes: Scotland’s coastal and intertidal zones and maritime hinterland encompass in-shore islands, trans-continental shipping lanes, ports and harbours, and transport infrastructure to intertidal fish-traps, and define understanding and conceptualisation of the liminal zone between the land and the sea. Due to the pervasive nature of the Marine and Maritime historic landscape, a holistic approach should be taken that incorporates evidence from a variety of sources including commercial and research archaeology, local and national societies, off-shore and onshore commercial development; and including studies derived from, but not limited to history, ethnology, cultural studies, folklore and architecture and involving a wide range of recording techniques ranging from photography, laser imaging, and sonar survey through to more orthodox drawn survey and excavation. 4. Collaboration: As is implicit in all the above, multi-disciplinary, collaborative, and cross-sector approaches are essential in order to ensure the capacity to meet the research challenges of the marine and maritime historic environment. There is a need for collaboration across the heritage sector and beyond, into specific areas of industry, science and the arts. Methods of communication amongst the constituent research individuals, institutions and networks should be developed, and dissemination of research results promoted. The formation of research communities, especially virtual centres of excellence, should be encouraged in order to build capacity.

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Rankin, Nicole, Deborah McGregor, Candice Donnelly, Bethany Van Dort, Richard De Abreu Lourenco, Anne Cust e Emily Stone. Lung cancer screening using low-dose computed tomography for high risk populations: Investigating effectiveness and screening program implementation considerations: An Evidence Check rapid review brokered by the Sax Institute (www.saxinstitute.org.au) for the Cancer Institute NSW. The Sax Institute, outubro de 2019. http://dx.doi.org/10.57022/clzt5093.

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Background Lung cancer is the number one cause of cancer death worldwide.(1) It is the fifth most commonly diagnosed cancer in Australia (12,741 cases diagnosed in 2018) and the leading cause of cancer death.(2) The number of years of potential life lost to lung cancer in Australia is estimated to be 58,450, similar to that of colorectal and breast cancer combined.(3) While tobacco control strategies are most effective for disease prevention in the general population, early detection via low dose computed tomography (LDCT) screening in high-risk populations is a viable option for detecting asymptomatic disease in current (13%) and former (24%) Australian smokers.(4) The purpose of this Evidence Check review is to identify and analyse existing and emerging evidence for LDCT lung cancer screening in high-risk individuals to guide future program and policy planning. Evidence Check questions This review aimed to address the following questions: 1. What is the evidence for the effectiveness of lung cancer screening for higher-risk individuals? 2. What is the evidence of potential harms from lung cancer screening for higher-risk individuals? 3. What are the main components of recent major lung cancer screening programs or trials? 4. What is the cost-effectiveness of lung cancer screening programs (include studies of cost–utility)? Summary of methods The authors searched the peer-reviewed literature across three databases (MEDLINE, PsycINFO and Embase) for existing systematic reviews and original studies published between 1 January 2009 and 8 August 2019. Fifteen systematic reviews (of which 8 were contemporary) and 64 original publications met the inclusion criteria set across the four questions. Key findings Question 1: What is the evidence for the effectiveness of lung cancer screening for higher-risk individuals? There is sufficient evidence from systematic reviews and meta-analyses of combined (pooled) data from screening trials (of high-risk individuals) to indicate that LDCT examination is clinically effective in reducing lung cancer mortality. In 2011, the landmark National Lung Cancer Screening Trial (NLST, a large-scale randomised controlled trial [RCT] conducted in the US) reported a 20% (95% CI 6.8% – 26.7%; P=0.004) relative reduction in mortality among long-term heavy smokers over three rounds of annual screening. High-risk eligibility criteria was defined as people aged 55–74 years with a smoking history of ≥30 pack-years (years in which a smoker has consumed 20-plus cigarettes each day) and, for former smokers, ≥30 pack-years and have quit within the past 15 years.(5) All-cause mortality was reduced by 6.7% (95% CI, 1.2% – 13.6%; P=0.02). Initial data from the second landmark RCT, the NEderlands-Leuvens Longkanker Screenings ONderzoek (known as the NELSON trial), have found an even greater reduction of 26% (95% CI, 9% – 41%) in lung cancer mortality, with full trial results yet to be published.(6, 7) Pooled analyses, including several smaller-scale European LDCT screening trials insufficiently powered in their own right, collectively demonstrate a statistically significant reduction in lung cancer mortality (RR 0.82, 95% CI 0.73–0.91).(8) Despite the reduction in all-cause mortality found in the NLST, pooled analyses of seven trials found no statistically significant difference in all-cause mortality (RR 0.95, 95% CI 0.90–1.00).(8) However, cancer-specific mortality is currently the most relevant outcome in cancer screening trials. These seven trials demonstrated a significantly greater proportion of early stage cancers in LDCT groups compared with controls (RR 2.08, 95% CI 1.43–3.03). Thus, when considering results across mortality outcomes and early stage cancers diagnosed, LDCT screening is considered to be clinically effective. Question 2: What is the evidence of potential harms from lung cancer screening for higher-risk individuals? The harms of LDCT lung cancer screening include false positive tests and the consequences of unnecessary invasive follow-up procedures for conditions that are eventually diagnosed as benign. While LDCT screening leads to an increased frequency of invasive procedures, it does not result in greater mortality soon after an invasive procedure (in trial settings when compared with the control arm).(8) Overdiagnosis, exposure to radiation, psychological distress and an impact on quality of life are other known harms. Systematic review evidence indicates the benefits of LDCT screening are likely to outweigh the harms. The potential harms are likely to be reduced as refinements are made to LDCT screening protocols through: i) the application of risk predication models (e.g. the PLCOm2012), which enable a more accurate selection of the high-risk population through the use of specific criteria (beyond age and smoking history); ii) the use of nodule management algorithms (e.g. Lung-RADS, PanCan), which assist in the diagnostic evaluation of screen-detected nodules and cancers (e.g. more precise volumetric assessment of nodules); and, iii) more judicious selection of patients for invasive procedures. Recent evidence suggests a positive LDCT result may transiently increase psychological distress but does not have long-term adverse effects on psychological distress or health-related quality of life (HRQoL). With regards to smoking cessation, there is no evidence to suggest screening participation invokes a false sense of assurance in smokers, nor a reduction in motivation to quit. The NELSON and Danish trials found no difference in smoking cessation rates between LDCT screening and control groups. Higher net cessation rates, compared with general population, suggest those who participate in screening trials may already be motivated to quit. Question 3: What are the main components of recent major lung cancer screening programs or trials? There are no systematic reviews that capture the main components of recent major lung cancer screening trials and programs. We extracted evidence from original studies and clinical guidance documents and organised this into key groups to form a concise set of components for potential implementation of a national lung cancer screening program in Australia: 1. Identifying the high-risk population: recruitment, eligibility, selection and referral 2. Educating the public, people at high risk and healthcare providers; this includes creating awareness of lung cancer, the benefits and harms of LDCT screening, and shared decision-making 3. Components necessary for health services to deliver a screening program: a. Planning phase: e.g. human resources to coordinate the program, electronic data systems that integrate medical records information and link to an established national registry b. Implementation phase: e.g. human and technological resources required to conduct LDCT examinations, interpretation of reports and communication of results to participants c. Monitoring and evaluation phase: e.g. monitoring outcomes across patients, radiological reporting, compliance with established standards and a quality assurance program 4. Data reporting and research, e.g. audit and feedback to multidisciplinary teams, reporting outcomes to enhance international research into LDCT screening 5. Incorporation of smoking cessation interventions, e.g. specific programs designed for LDCT screening or referral to existing community or hospital-based services that deliver cessation interventions. Most original studies are single-institution evaluations that contain descriptive data about the processes required to establish and implement a high-risk population-based screening program. Across all studies there is a consistent message as to the challenges and complexities of establishing LDCT screening programs to attract people at high risk who will receive the greatest benefits from participation. With regards to smoking cessation, evidence from one systematic review indicates the optimal strategy for incorporating smoking cessation interventions into a LDCT screening program is unclear. There is widespread agreement that LDCT screening attendance presents a ‘teachable moment’ for cessation advice, especially among those people who receive a positive scan result. Smoking cessation is an area of significant research investment; for instance, eight US-based clinical trials are now underway that aim to address how best to design and deliver cessation programs within large-scale LDCT screening programs.(9) Question 4: What is the cost-effectiveness of lung cancer screening programs (include studies of cost–utility)? Assessing the value or cost-effectiveness of LDCT screening involves a complex interplay of factors including data on effectiveness and costs, and institutional context. A key input is data about the effectiveness of potential and current screening programs with respect to case detection, and the likely outcomes of treating those cases sooner (in the presence of LDCT screening) as opposed to later (in the absence of LDCT screening). Evidence about the cost-effectiveness of LDCT screening programs has been summarised in two systematic reviews. We identified a further 13 studies—five modelling studies, one discrete choice experiment and seven articles—that used a variety of methods to assess cost-effectiveness. Three modelling studies indicated LDCT screening was cost-effective in the settings of the US and Europe. Two studies—one from Australia and one from New Zealand—reported LDCT screening would not be cost-effective using NLST-like protocols. We anticipate that, following the full publication of the NELSON trial, cost-effectiveness studies will likely be updated with new data that reduce uncertainty about factors that influence modelling outcomes, including the findings of indeterminate nodules. Gaps in the evidence There is a large and accessible body of evidence as to the effectiveness (Q1) and harms (Q2) of LDCT screening for lung cancer. Nevertheless, there are significant gaps in the evidence about the program components that are required to implement an effective LDCT screening program (Q3). Questions about LDCT screening acceptability and feasibility were not explicitly included in the scope. However, as the evidence is based primarily on US programs and UK pilot studies, the relevance to the local setting requires careful consideration. The Queensland Lung Cancer Screening Study provides feasibility data about clinical aspects of LDCT screening but little about program design. The International Lung Screening Trial is still in the recruitment phase and findings are not yet available for inclusion in this Evidence Check. The Australian Population Based Screening Framework was developed to “inform decision-makers on the key issues to be considered when assessing potential screening programs in Australia”.(10) As the Framework is specific to population-based, rather than high-risk, screening programs, there is a lack of clarity about transferability of criteria. However, the Framework criteria do stipulate that a screening program must be acceptable to “important subgroups such as target participants who are from culturally and linguistically diverse backgrounds, Aboriginal and Torres Strait Islander people, people from disadvantaged groups and people with a disability”.(10) An extensive search of the literature highlighted that there is very little information about the acceptability of LDCT screening to these population groups in Australia. Yet they are part of the high-risk population.(10) There are also considerable gaps in the evidence about the cost-effectiveness of LDCT screening in different settings, including Australia. The evidence base in this area is rapidly evolving and is likely to include new data from the NELSON trial and incorporate data about the costs of targeted- and immuno-therapies as these treatments become more widely available in Australia.

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