The Experts below are selected from a list of 12 Experts worldwide ranked by ideXlab platform
Finn Hjortgaard Christensen - One of the best experts on this subject based on the ideXlab platform.
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Data set isolation for bibliometric online analyses of research publications fundamental methodological issues
Journal of the Association for Information Science and Technology, 1997Co-Authors: Peter Ingwersen, Finn Hjortgaard ChristensenAbstract:The aim of the article is to emphasize and illustrate the retrieval dimensions of Data Collection Activity pnline and their influence on the research evaluation outcome. The attempt is to reinforce the link between online retrieval and bibliometrics. Given that various forms of publication counts and citation analyses provide a valuable and revealing quantitative starting point for more qualitative indications and assessments of Science and Technology (S&T) performance, it is evident that their reliability and objectivity must be undisputed as far as possible. The article discusses the basic problems and limitations inherent in online bibliometric Data Collection and analyses, and points to possible solutions by means of illustrative case studies and examples. The reason for performing local publication analyses online often arises because of the increased use of external research assessments made by centralized bodies. For small institutions in small countries, like the North European one, such self-analyses may in addition provide valuable and inexpensive insights into novel S&T niches to explore. The major concern is the extent to which online bibliographic and domain dependent Databases, as a supplement to the Institute for Scientific Information (ISI) citation files, are suitable for quantitative analysis and mapping of R&D outcome. By merging these two different types of Databases into a single cluster, the method of duplicate removal becomes crucial. The article introduces a novel removal procedure by describing and exemplifying the principle of Reversed Duplicate Removal (RDR). RDR enables the analyst to take control of the location of the duplicates and to perform tailored analyses of the overlap of identical documents between files. It is well known that the Databases themselves present obstacles directly associated with the process of performing online retrieval of the information necessary for further analysis. Problems encountered are, for instance, poor or inconsistent subject indexing within a single Database or among several Databases. Name form inconsistencies as to authors, institutions, and journals, the lack or inaccessibility of vital Data in the Database structures, etc., also present obstacles. On the other hand, comprehensive online bibliometric analyses are in many ways easier, faster, and less expensive to perform locally than those made using the independent CD-ROM versions of the relevant Databases. In contrast to the online versions, the CD-ROM systems demonstrate a vital shortage of robust Data processing and manipulation facilities. The downloading of records from a variety of CD-ROM files, the cleaning-up process, and the ensuing Data processing activities become cumbersome and resource demanding. Regardless of Database versioning, the degree of awareness of these retrieval and set isolation factors, such as the relevant search commands, syntax, and the analysis assumptions on the part of the analyst, plays an important role for the quality of the analysis outcome.
Peter Ingwersen - One of the best experts on this subject based on the ideXlab platform.
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Data set isolation for bibliometric online analyses of research publications fundamental methodological issues
Journal of the Association for Information Science and Technology, 1997Co-Authors: Peter Ingwersen, Finn Hjortgaard ChristensenAbstract:The aim of the article is to emphasize and illustrate the retrieval dimensions of Data Collection Activity pnline and their influence on the research evaluation outcome. The attempt is to reinforce the link between online retrieval and bibliometrics. Given that various forms of publication counts and citation analyses provide a valuable and revealing quantitative starting point for more qualitative indications and assessments of Science and Technology (S&T) performance, it is evident that their reliability and objectivity must be undisputed as far as possible. The article discusses the basic problems and limitations inherent in online bibliometric Data Collection and analyses, and points to possible solutions by means of illustrative case studies and examples. The reason for performing local publication analyses online often arises because of the increased use of external research assessments made by centralized bodies. For small institutions in small countries, like the North European one, such self-analyses may in addition provide valuable and inexpensive insights into novel S&T niches to explore. The major concern is the extent to which online bibliographic and domain dependent Databases, as a supplement to the Institute for Scientific Information (ISI) citation files, are suitable for quantitative analysis and mapping of R&D outcome. By merging these two different types of Databases into a single cluster, the method of duplicate removal becomes crucial. The article introduces a novel removal procedure by describing and exemplifying the principle of Reversed Duplicate Removal (RDR). RDR enables the analyst to take control of the location of the duplicates and to perform tailored analyses of the overlap of identical documents between files. It is well known that the Databases themselves present obstacles directly associated with the process of performing online retrieval of the information necessary for further analysis. Problems encountered are, for instance, poor or inconsistent subject indexing within a single Database or among several Databases. Name form inconsistencies as to authors, institutions, and journals, the lack or inaccessibility of vital Data in the Database structures, etc., also present obstacles. On the other hand, comprehensive online bibliometric analyses are in many ways easier, faster, and less expensive to perform locally than those made using the independent CD-ROM versions of the relevant Databases. In contrast to the online versions, the CD-ROM systems demonstrate a vital shortage of robust Data processing and manipulation facilities. The downloading of records from a variety of CD-ROM files, the cleaning-up process, and the ensuing Data processing activities become cumbersome and resource demanding. Regardless of Database versioning, the degree of awareness of these retrieval and set isolation factors, such as the relevant search commands, syntax, and the analysis assumptions on the part of the analyst, plays an important role for the quality of the analysis outcome.
V Dongen - One of the best experts on this subject based on the ideXlab platform.
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testing of traffic information service broadcast tis b and ads b at memphis international airport
Proceedings. The 21st Digital Avionics Systems Conference, 2002Co-Authors: R Nichols, D J Bernays, T Spriesterbach, V DongenAbstract:Automatic dependent surveillance broadcast (ADS-B) is a surveillance system in which participating aircraft periodically distribute estimates of their state vector on a common communications channel. The state vector estimates are derived from navigation avionics on each individual aircraft. Any user may then assemble a surveillance picture of nearby traffic by collecting these reports and comparing them to their own position. Of course, such a surveillance picture only includes aircraft that are equipped with ADS-B avionics and are transmitting their state vector updates. While in the end state one can envision near universal equipage, "early adopters" of ADS-B receivers will gain little utility until a significant fraction of the fleet equips. Traffic information system broadcast (TIS-B) is a tool to bridge this transition. TIS-B collects state vector information on aircraft through ground-based surveillance sensors, reformats the information into "ADS-B-like" formats, and broadcasts these reports on the common ADS-B channel. This paper describes the test organization and preliminary results from a Data Collection Activity conducted jointly by FAA and industry from May 20-23 at Memphis International Airport to characterize key elements of TIS-B.
R Nichols - One of the best experts on this subject based on the ideXlab platform.
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testing of traffic information service broadcast tis b and ads b at memphis international airport
Proceedings. The 21st Digital Avionics Systems Conference, 2002Co-Authors: R Nichols, D J Bernays, T Spriesterbach, V DongenAbstract:Automatic dependent surveillance broadcast (ADS-B) is a surveillance system in which participating aircraft periodically distribute estimates of their state vector on a common communications channel. The state vector estimates are derived from navigation avionics on each individual aircraft. Any user may then assemble a surveillance picture of nearby traffic by collecting these reports and comparing them to their own position. Of course, such a surveillance picture only includes aircraft that are equipped with ADS-B avionics and are transmitting their state vector updates. While in the end state one can envision near universal equipage, "early adopters" of ADS-B receivers will gain little utility until a significant fraction of the fleet equips. Traffic information system broadcast (TIS-B) is a tool to bridge this transition. TIS-B collects state vector information on aircraft through ground-based surveillance sensors, reformats the information into "ADS-B-like" formats, and broadcasts these reports on the common ADS-B channel. This paper describes the test organization and preliminary results from a Data Collection Activity conducted jointly by FAA and industry from May 20-23 at Memphis International Airport to characterize key elements of TIS-B.
D J Bernays - One of the best experts on this subject based on the ideXlab platform.
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testing of traffic information service broadcast tis b and ads b at memphis international airport
Proceedings. The 21st Digital Avionics Systems Conference, 2002Co-Authors: R Nichols, D J Bernays, T Spriesterbach, V DongenAbstract:Automatic dependent surveillance broadcast (ADS-B) is a surveillance system in which participating aircraft periodically distribute estimates of their state vector on a common communications channel. The state vector estimates are derived from navigation avionics on each individual aircraft. Any user may then assemble a surveillance picture of nearby traffic by collecting these reports and comparing them to their own position. Of course, such a surveillance picture only includes aircraft that are equipped with ADS-B avionics and are transmitting their state vector updates. While in the end state one can envision near universal equipage, "early adopters" of ADS-B receivers will gain little utility until a significant fraction of the fleet equips. Traffic information system broadcast (TIS-B) is a tool to bridge this transition. TIS-B collects state vector information on aircraft through ground-based surveillance sensors, reformats the information into "ADS-B-like" formats, and broadcasts these reports on the common ADS-B channel. This paper describes the test organization and preliminary results from a Data Collection Activity conducted jointly by FAA and industry from May 20-23 at Memphis International Airport to characterize key elements of TIS-B.
