Pectrum Sharing of VHF Data Exchange Satellite System

Abstract The civilian Automatic Identification System (AIS) has no inherent protection against spoofing. Spoofed AIS messages have the potential to interfere with the safe navigation of a vessel by, amongst other approaches, spoofing maritime virtual aids to navigation and/or differential global navigation satellite system (DGNSS) correction data conveyed across it. Acting maliciously, a single transmitter may spoof thousands of AIS messages per minute with the potential to cause considerable nuisance; compromising information provided by AIS intended to enhance the mariner's situational awareness. This work describes an approach to authenticate AIS messages using public key cryptography (PKC) and thus provide unequivocal evidence that AIS messages originate from genuine sources and so can be trusted. Improvements to the proposed AIS authentication scheme are identified which address a security weakness and help avoid false positives to spoofing caused by changes to message syntax. A channel loading investigation concludes that sufficient bandwidth is available to routinely authenticate all AIS messages whilst retaining backwards compatibility by carrying PKC ‘digital signatures’ in a separate VHF Data Exchange System (VDES) side channel.

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A new permanent multi-parameter monitoring network in Central Asian high mountains – from measurements to data bases

Geoscientific Instrumentation Methods and Data Systems ◽

10.5194/gi-2-97-2013 ◽

2013 ◽

Vol 2 (1) ◽

pp. 97-111 ◽

Cited By ~ 17

Author(s):

T. Schöne ◽

C. Zech ◽

K. Unger-Shayesteh ◽

V. Rudenko ◽

H. Thoss ◽

...

Keyword(s):

Data Exchange ◽

Monitoring Network ◽

Satellite System ◽

Hydrological Parameters ◽

Long Term Storage ◽

Central Asian ◽

Seismic Sensors ◽

Global Navigation Satellite ◽

Gnss Data

Abstract. Long-term monitoring of water resources and climate parameters at the scale of river basins requires networks of continuously operated in-situ stations. Since 2009, GFZ and CAIAG, in cooperation with the National Hydrometeorological Services (NHMS) of Central Asia, are establishing such a regional monitoring network in Kazakhstan, Kyrgyzstan, Tajikistan, Uzbekistan, and lately Afghanistan to collect observations of meteorological and hydrological parameters and to deliver them to the end-users for operational tasks and scientific studies. The newly developed and installed remotely operated multi-parameter stations (ROMPS) do not only monitor standard meteorological and hydrological parameters, but also deliver Global Navigation Satellite System (GNSS) data for atmospheric sounding as well as tectonic studies. Additionally, three stations integrate seismic sensors for earthquake monitoring. The observational data from the ROMPS is transmitted nominally in near-real time, but at least once a day to a centralized geo-database infrastructure for long-term storage and data redistribution. Users can access the data manually using a web-interface or automatically using SOS requests; in addition, data is planed to be distributed to the NHMS through standard communication and data exchange channels.

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Research on high speed data distribution technology based on kernel state of domestic operating system

MATEC Web of Conferences ◽

10.1051/matecconf/202030904019 ◽

2020 ◽

Vol 309 ◽

pp. 04019

Author(s):

Shumin Geng ◽

Wei Wang ◽

Xinlei Yang ◽

Peng Du ◽

Hui Qiao

Keyword(s):

Operating System ◽

Data Transmission ◽

High Speed ◽

Data Exchange ◽

Design Method ◽

Data Distribution ◽

Satellite System ◽

Test Environment ◽

User Data ◽

Transmission Ability

The data distribution platform is the ground information center of the relay satellite system to realize the data relay ability. With the increasing demand of the user data transmission, the data transmission ability of the relay satellite system is increasing. The increasing data transmission ability of the satellite puts forward higher requirements for the data distribution ability of the ground distribution platform. In this paper, the technology of data acquisition and data exchange based on the kernel state of the domestic operating system is studied. The design method of data distribution platform based on the kernel state programming of the domestic operating system is proposed. The simulation test environment is built to verify the effectiveness of the method, which can greatly improve the data processing ability of a single data distribution device, significantly reduce the scale of data distribution device, it provides strong technical support for building a new model of intensive and efficient data distribution.

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Study on Equipment Quality Monitoring Information Transmission System Based on BeiDou Navigation Satellite System Short Message Communication

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.602-605.3712 ◽

2014 ◽

Vol 602-605 ◽

pp. 3712-3715

Author(s):

Da Quan Deng ◽

Wan Lin Li ◽

Yan Chen ◽

Fang Zhao

Keyword(s):

Management System ◽

Data Exchange ◽

Information Quality ◽

Satellite System ◽

Quality Monitoring ◽

Equipment Management ◽

Short Message ◽

Data Exchange Network ◽

Exchange Network ◽

Wide Geographic Distribution

Because the equipment management of wide geographic distribution and it is difficult to obtain real-time equipment quality status for the equipment management system. The system built a quality monitoring and management system of distributed equipment, formed the command and data exchange network based on Beidou satellite system, achieved the timely transmission of information quality monitoring equipment, accurated grasp equipment status, realized the equipment safeguard informatization, accurated security provides the means to support.

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Machine-Scored Syntax: Comparison of the CLAN Automatic Scoring Program to Manual Scoring

Language Speech and Hearing Services in Schools ◽

10.1044/2019_lshss-19-00056 ◽

2020 ◽

Vol 51 (2) ◽

pp. 479-493

Author(s):

Jenny A. Roberts ◽

Evelyn P. Altenberg ◽

Madison Hunter

Keyword(s):

Data Exchange ◽

Child Language ◽

Exchange System ◽

Absolute Point ◽

Language Analysis ◽

Search Patterns ◽

Language Data ◽

Report Accuracy ◽

Point To Point ◽

Automatic Scoring

Purpose The results of automatic machine scoring of the Index of Productive Syntax from the Computerized Language ANalysis (CLAN) tools of the Child Language Data Exchange System of TalkBank (MacWhinney, 2000) were compared to manual scoring to determine the accuracy of the machine-scored method. Method Twenty transcripts of 10 children from archival data of the Weismer Corpus from the Child Language Data Exchange System at 30 and 42 months were examined. Measures of absolute point difference and point-to-point accuracy were compared, as well as points erroneously given and missed. Two new measures for evaluating automatic scoring of the Index of Productive Syntax were introduced: Machine Item Accuracy (MIA) and Cascade Failure Rate— these measures further analyze points erroneously given and missed. Differences in total scores, subscale scores, and individual structures were also reported. Results Mean absolute point difference between machine and hand scoring was 3.65, point-to-point agreement was 72.6%, and MIA was 74.9%. There were large differences in subscales, with Noun Phrase and Verb Phrase subscales generally providing greater accuracy and agreement than Question/Negation and Sentence Structures subscales. There were significantly more erroneous than missed items in machine scoring, attributed to problems of mistagging of elements, imprecise search patterns, and other errors. Cascade failure resulted in an average of 4.65 points lost per transcript. Conclusions The CLAN program showed relatively inaccurate outcomes in comparison to manual scoring on both traditional and new measures of accuracy. Recommendations for improvement of the program include accounting for second exemplar violations and applying cascaded credit, among other suggestions. It was proposed that research on machine-scored syntax routinely report accuracy measures detailing erroneous and missed scores, including MIA, so that researchers and clinicians are aware of the limitations of a machine-scoring program. Supplemental Material https://doi.org/10.23641/asha.11984364

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