Pub Date : 2004-10-24DOI: 10.1109/DASC.2004.1390806
K.Y. Hayhurst
When it comes to software engineering technologies, enthusiastic boasts about production efficiencies are more common than sober discussions about technical difficulties - that is the nature of marketing. However, understanding potential technical difficulties in new technologies is essential, particularly, when it comes to using these technologies in safety-critical systems. Such is the case with object oriented technology (OOT). In 2001, the Federal Aviation Administration (FAA) and the National Aeronautics and Space Administration (NASA) started the object oriented technology in aviation (OOTiA) project to facilitate safe use of OOT in aviation applications. A primary objective of the project was to identify and document safety and certification concerns about using OOT in compliance with RTCA/DO-178B software considerations in aircraft equipment and system certification. This work provides a brief survey of the technical challenges that have been identified so far.
{"title":"Technical challenges in using object oriented technology in aviation applications","authors":"K.Y. Hayhurst","doi":"10.1109/DASC.2004.1390806","DOIUrl":"https://doi.org/10.1109/DASC.2004.1390806","url":null,"abstract":"When it comes to software engineering technologies, enthusiastic boasts about production efficiencies are more common than sober discussions about technical difficulties - that is the nature of marketing. However, understanding potential technical difficulties in new technologies is essential, particularly, when it comes to using these technologies in safety-critical systems. Such is the case with object oriented technology (OOT). In 2001, the Federal Aviation Administration (FAA) and the National Aeronautics and Space Administration (NASA) started the object oriented technology in aviation (OOTiA) project to facilitate safe use of OOT in aviation applications. A primary objective of the project was to identify and document safety and certification concerns about using OOT in compliance with RTCA/DO-178B software considerations in aircraft equipment and system certification. This work provides a brief survey of the technical challenges that have been identified so far.","PeriodicalId":422463,"journal":{"name":"The 23rd Digital Avionics Systems Conference (IEEE Cat. No.04CH37576)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123870754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-10-24DOI: 10.1109/DASC.2004.1390731
Fahmida Chowdhury, Celeste U Belcastro, Bin Jiang
Residuals are typically used as indicators of normal (non-faulty) vs. abnormal (faulty) behavior in dynamic systems. The nonfaulty residuals are assumed to be Gaussian, zero-mean, uncorrelated, with a known variance. However, in many practical situations, the assumption of Gaussian-ness may not be valid. We propose a new type of fault detector which is essentially independent of the distribution of the residuals. This fault detector is based on an autoregressive modeling of the residual signal, augmented by a sample variance calculation. Usefulness of this new detector is demonstrated with the experimental fault data obtained at NASA Langley Research Center.
{"title":"Fault detection: the effect of unknown distribution of residuals","authors":"Fahmida Chowdhury, Celeste U Belcastro, Bin Jiang","doi":"10.1109/DASC.2004.1390731","DOIUrl":"https://doi.org/10.1109/DASC.2004.1390731","url":null,"abstract":"Residuals are typically used as indicators of normal (non-faulty) vs. abnormal (faulty) behavior in dynamic systems. The nonfaulty residuals are assumed to be Gaussian, zero-mean, uncorrelated, with a known variance. However, in many practical situations, the assumption of Gaussian-ness may not be valid. We propose a new type of fault detector which is essentially independent of the distribution of the residuals. This fault detector is based on an autoregressive modeling of the residual signal, augmented by a sample variance calculation. Usefulness of this new detector is demonstrated with the experimental fault data obtained at NASA Langley Research Center.","PeriodicalId":422463,"journal":{"name":"The 23rd Digital Avionics Systems Conference (IEEE Cat. No.04CH37576)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124085932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-10-24DOI: 10.1109/DASC.2004.1391262
Hhnur Jdhannsson, Ebba W r a Hvannberg
Communication and surveillance capabilities in oceanic air traffic control are improving and the amount of air traffic increases significantly over the next decades. This requires new systems and procedures to be incorporated into the oceanic air traffic controller workstation. The Icelandic Civil Aviation Administration (ICAA) is looking at ways to integrate the current set of user interfaces used at Reykjavik Oceanic Center in an effort to increase controller performance. The workstation consists of three different user interfaces, the flight data processing systems (FDPS), which presents electronic flight strips to the controller, the radar display, which displays radar data and the situation display, which is a backup system for the FDPS system. Three approaches for integration are presented and claims analysis used to select between them. The result of the claims analysis and controllers' preference was a spatial display where the FDPS system is integrated into the radar display. A paper prototype was created and presented to qualified air traffic controllers in order to get feedback on the prototype design as well as the transition from a temporal display to spatial display. This paper discusses the prototype design and the results from two user-testing sessions at ICAA.
{"title":"Integration of air traffic control user interfaces","authors":"Hhnur Jdhannsson, Ebba W r a Hvannberg","doi":"10.1109/DASC.2004.1391262","DOIUrl":"https://doi.org/10.1109/DASC.2004.1391262","url":null,"abstract":"Communication and surveillance capabilities in oceanic air traffic control are improving and the amount of air traffic increases significantly over the next decades. This requires new systems and procedures to be incorporated into the oceanic air traffic controller workstation. The Icelandic Civil Aviation Administration (ICAA) is looking at ways to integrate the current set of user interfaces used at Reykjavik Oceanic Center in an effort to increase controller performance. The workstation consists of three different user interfaces, the flight data processing systems (FDPS), which presents electronic flight strips to the controller, the radar display, which displays radar data and the situation display, which is a backup system for the FDPS system. Three approaches for integration are presented and claims analysis used to select between them. The result of the claims analysis and controllers' preference was a spatial display where the FDPS system is integrated into the radar display. A paper prototype was created and presented to qualified air traffic controllers in order to get feedback on the prototype design as well as the transition from a temporal display to spatial display. This paper discusses the prototype design and the results from two user-testing sessions at ICAA.","PeriodicalId":422463,"journal":{"name":"The 23rd Digital Avionics Systems Conference (IEEE Cat. No.04CH37576)","volume":"31 9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127646064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-10-24DOI: 10.1109/DASC.2004.1390789
L. Jenkins, A. Bennett
As we enter the 21/sup st/ century, the system engineering challenge of thermal management of digital avionics is intensifying. The functional need for faster, smaller devices is pressing systems to their mechanical and physical limits. At present, thermal management is widely seen as a secondary issue, needed only for reliability of the components. The goal of this paper is to show that thermal management is becoming more than a reliability factor in digital avionics. It is a fundamental driver in the development of the architecture for advance designs. Thermal design is integral in meeting the functional design requirements of systems, especially as the drive to lower cost, move systems to use more common commercial devices and subsystems. This paper address some of the impacts this design process has on avionics system performance, and how these impacts affect the system engineering requirements of the air vehicle. Thermal management must be an integral part of the air vehicle and avionic systems design to ensure system engineering success. The goal of this paper is to give a clearer picture of the challenges we face in addressing thermal management issues. One topic that is explored is how functional performance can be severely compromised in systems where the design is driven primarily by TM. We need to better understand the dynamics of trading weight which may be directly linked to the thermal management challenge. We want to show the relevance of thermal management design requirements to architecture development of avionics systems. To get the best system, the entire dynamic picture of how thermal management ties in, with electrical and physical design is needed to achieve the desired efficiency and effectiveness in the 21/sup st/ century systems.
{"title":"21st century challenge: thermal management design requirements","authors":"L. Jenkins, A. Bennett","doi":"10.1109/DASC.2004.1390789","DOIUrl":"https://doi.org/10.1109/DASC.2004.1390789","url":null,"abstract":"As we enter the 21/sup st/ century, the system engineering challenge of thermal management of digital avionics is intensifying. The functional need for faster, smaller devices is pressing systems to their mechanical and physical limits. At present, thermal management is widely seen as a secondary issue, needed only for reliability of the components. The goal of this paper is to show that thermal management is becoming more than a reliability factor in digital avionics. It is a fundamental driver in the development of the architecture for advance designs. Thermal design is integral in meeting the functional design requirements of systems, especially as the drive to lower cost, move systems to use more common commercial devices and subsystems. This paper address some of the impacts this design process has on avionics system performance, and how these impacts affect the system engineering requirements of the air vehicle. Thermal management must be an integral part of the air vehicle and avionic systems design to ensure system engineering success. The goal of this paper is to give a clearer picture of the challenges we face in addressing thermal management issues. One topic that is explored is how functional performance can be severely compromised in systems where the design is driven primarily by TM. We need to better understand the dynamics of trading weight which may be directly linked to the thermal management challenge. We want to show the relevance of thermal management design requirements to architecture development of avionics systems. To get the best system, the entire dynamic picture of how thermal management ties in, with electrical and physical design is needed to achieve the desired efficiency and effectiveness in the 21/sup st/ century systems.","PeriodicalId":422463,"journal":{"name":"The 23rd Digital Avionics Systems Conference (IEEE Cat. No.04CH37576)","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129047103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-10-24DOI: 10.1109/DASC.2004.1391301
P. Manzi, L. Lindberg, K. Wichman, O. Bleeker, S. Langhans
As our industry continues to grow, new methods will be needed to increase capacity and efficiency in the ATM system. Existing technology, already onboard many of today's airplanes can be used to greatly increase the efficiency and capacity of the ATM system for all of the operating domains. This paper aims to show how a system based on control along an optimized vertical and lateral path to the runway can be used to enhance operational efficiency, safety and reduce emissions in the airline, airport and ATM sectors. The paper will explore the current system, present a target concept based on aircraft trajectory information for the future system, and present applications and benefits that can be derived from the target concept. In addition, the paper will show how the next step towards implementation and validation of the target concept will take place.
{"title":"Improving operational efficiency in the airport, airline and ATM processes","authors":"P. Manzi, L. Lindberg, K. Wichman, O. Bleeker, S. Langhans","doi":"10.1109/DASC.2004.1391301","DOIUrl":"https://doi.org/10.1109/DASC.2004.1391301","url":null,"abstract":"As our industry continues to grow, new methods will be needed to increase capacity and efficiency in the ATM system. Existing technology, already onboard many of today's airplanes can be used to greatly increase the efficiency and capacity of the ATM system for all of the operating domains. This paper aims to show how a system based on control along an optimized vertical and lateral path to the runway can be used to enhance operational efficiency, safety and reduce emissions in the airline, airport and ATM sectors. The paper will explore the current system, present a target concept based on aircraft trajectory information for the future system, and present applications and benefits that can be derived from the target concept. In addition, the paper will show how the next step towards implementation and validation of the target concept will take place.","PeriodicalId":422463,"journal":{"name":"The 23rd Digital Avionics Systems Conference (IEEE Cat. No.04CH37576)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115850767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-10-24DOI: 10.1109/DASC.2004.1390726
C. Hote
In this document, we discuss the power of abstract semantics analysis, a breakthrough technique that has been successfully applied to solve traditional software testing challenges in the embedded systems industry. This approach radically departs from conventional testing as it does not rely on random tests to analyze code robustness. The paper addresses what abstract semantics analysis is, how the technique works and why it is a more effective solution to run-time error detection and debugging.
{"title":"Next generation testing tecrnique for embedded software: abstract semantics analysis","authors":"C. Hote","doi":"10.1109/DASC.2004.1390726","DOIUrl":"https://doi.org/10.1109/DASC.2004.1390726","url":null,"abstract":"In this document, we discuss the power of abstract semantics analysis, a breakthrough technique that has been successfully applied to solve traditional software testing challenges in the embedded systems industry. This approach radically departs from conventional testing as it does not rely on random tests to analyze code robustness. The paper addresses what abstract semantics analysis is, how the technique works and why it is a more effective solution to run-time error detection and debugging.","PeriodicalId":422463,"journal":{"name":"The 23rd Digital Avionics Systems Conference (IEEE Cat. No.04CH37576)","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116377856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-10-24DOI: 10.1109/DASC.2004.1390831
I. Wilson
{"title":"Extension of a real time simulator to provide live displays, voice over IP and CPDLC for a global CNS system - [Not available for publication]","authors":"I. Wilson","doi":"10.1109/DASC.2004.1390831","DOIUrl":"https://doi.org/10.1109/DASC.2004.1390831","url":null,"abstract":"","PeriodicalId":422463,"journal":{"name":"The 23rd Digital Avionics Systems Conference (IEEE Cat. No.04CH37576)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117053803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-10-24DOI: 10.1109/DASC.2004.1391325
S. Kakarlapudi, M. Uijt de Haag
This paper describes image analysis techniques that can be used for the comparison of terrain profiles obtained from a weather radar (WxR) in ground-mapping mode and the terrain information stored in a database. A synthetic vision system (SVS) provides the pilot with a virtual display of the surrounding environment to improve the situational awareness and reduce the number of aviation accidents caused by controlled flight into terrain. If the databases used for generating an SVS display do not have a quantifiable level of integrity, an integrity monitor may be a critical subsystem whose inclusion may guarantee the required integrity level in the terrain databases. The terrain information available for processing during the entire flight path is the stored terrain database and data obtained from onboard sensors. Integrity monitoring (IM) is done by making a comparison of these available data. The onboard sensor used for analysis in this research is a forward looking sensor, WxR. The comparison of the WxR data and the terrain database requires a common domain representation. This paper describes the generation of a common domain image representation from the WxR data and the terrain database and possible image analysis techniques to compare these images. The main feature used for the comparison of the images is the shadow region. The algorithms are tested using data obtained from a series of flight tests, one of which was conducted at Juneau, Alaska by Ohio University. The similarity results obtained are used as a criterion to determine any horizontal bias existent in the database.
{"title":"The application of image analysis techniques to forward looking terrain database integrity monitoring","authors":"S. Kakarlapudi, M. Uijt de Haag","doi":"10.1109/DASC.2004.1391325","DOIUrl":"https://doi.org/10.1109/DASC.2004.1391325","url":null,"abstract":"This paper describes image analysis techniques that can be used for the comparison of terrain profiles obtained from a weather radar (WxR) in ground-mapping mode and the terrain information stored in a database. A synthetic vision system (SVS) provides the pilot with a virtual display of the surrounding environment to improve the situational awareness and reduce the number of aviation accidents caused by controlled flight into terrain. If the databases used for generating an SVS display do not have a quantifiable level of integrity, an integrity monitor may be a critical subsystem whose inclusion may guarantee the required integrity level in the terrain databases. The terrain information available for processing during the entire flight path is the stored terrain database and data obtained from onboard sensors. Integrity monitoring (IM) is done by making a comparison of these available data. The onboard sensor used for analysis in this research is a forward looking sensor, WxR. The comparison of the WxR data and the terrain database requires a common domain representation. This paper describes the generation of a common domain image representation from the WxR data and the terrain database and possible image analysis techniques to compare these images. The main feature used for the comparison of the images is the shadow region. The algorithms are tested using data obtained from a series of flight tests, one of which was conducted at Juneau, Alaska by Ohio University. The similarity results obtained are used as a criterion to determine any horizontal bias existent in the database.","PeriodicalId":422463,"journal":{"name":"The 23rd Digital Avionics Systems Conference (IEEE Cat. No.04CH37576)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117249795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-10-24DOI: 10.1109/DASC.2004.1391288
F. Bussink, N. Doble, B. Barmore, S. Singer
As part of NASA's distributed air/ground traffic management (DAG-TM) effort, NASA Langley Research Center is developing concepts and algorithms for merging multiple aircraft arrival streams and precisely spacing aircraft over the runway threshold. An airborne tool has been created for this purpose, called airborne merging and spacing for terminal arrivals (AMSTAR). To evaluate the performance of AMSTAR and complement human-in-the-loop experiments, a simulation environment has been developed that enables fast-time studies of AMSTAR operations. The environment is based on TMX, a multiple-aircraft desktop simulation program created by the Netherlands National Aerospace Laboratory (NLR). This paper reviews the AMSTAR concept, discusses the integration of the AMSTAR algorithm into TMX and the enhancements added to TMX to support fast-time AMSTAR studies, and presents initial simulation results.
{"title":"A fast-time simulation environment for airborne merging and spacing research","authors":"F. Bussink, N. Doble, B. Barmore, S. Singer","doi":"10.1109/DASC.2004.1391288","DOIUrl":"https://doi.org/10.1109/DASC.2004.1391288","url":null,"abstract":"As part of NASA's distributed air/ground traffic management (DAG-TM) effort, NASA Langley Research Center is developing concepts and algorithms for merging multiple aircraft arrival streams and precisely spacing aircraft over the runway threshold. An airborne tool has been created for this purpose, called airborne merging and spacing for terminal arrivals (AMSTAR). To evaluate the performance of AMSTAR and complement human-in-the-loop experiments, a simulation environment has been developed that enables fast-time studies of AMSTAR operations. The environment is based on TMX, a multiple-aircraft desktop simulation program created by the Netherlands National Aerospace Laboratory (NLR). This paper reviews the AMSTAR concept, discusses the integration of the AMSTAR algorithm into TMX and the enhancements added to TMX to support fast-time AMSTAR studies, and presents initial simulation results.","PeriodicalId":422463,"journal":{"name":"The 23rd Digital Avionics Systems Conference (IEEE Cat. No.04CH37576)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117196904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2004-10-24DOI: 10.1109/DASC.2004.1391305
M. Malaek, J. Parastari
In this paper, the problem of designing optimal conflict-free maneuvers for multiple aircraft encounters is studied. The proposed maneuvers are based on changes of heading, speed and maneuvering time. The optimality of maneuvers among the conflict-free constraint is based on minimization of a certain cost function based on kinetic energy of either aircraft involved. Some suitable priority weight factors are incorporated into the cost function so that optimal resolution maneuvers are such that aircraft with lower priorities assume more responsibility in resolving the conflicts. As for considering aircraft turning dynamics, the circular 3-arced path with constant speed are proposed for each aircraft maneuver rather than the well known optimal two-legged solutions. Fairly thorough simulations have been done to evaluate the effectiveness of the methodology, while some are presented here to illustrate the effectiveness of the proposed algorithms for real time conflict resolution.
{"title":"Optimal circular 3-arced with constant speed coordinated maneuvers for planar multi aircraft conflict resolution","authors":"M. Malaek, J. Parastari","doi":"10.1109/DASC.2004.1391305","DOIUrl":"https://doi.org/10.1109/DASC.2004.1391305","url":null,"abstract":"In this paper, the problem of designing optimal conflict-free maneuvers for multiple aircraft encounters is studied. The proposed maneuvers are based on changes of heading, speed and maneuvering time. The optimality of maneuvers among the conflict-free constraint is based on minimization of a certain cost function based on kinetic energy of either aircraft involved. Some suitable priority weight factors are incorporated into the cost function so that optimal resolution maneuvers are such that aircraft with lower priorities assume more responsibility in resolving the conflicts. As for considering aircraft turning dynamics, the circular 3-arced path with constant speed are proposed for each aircraft maneuver rather than the well known optimal two-legged solutions. Fairly thorough simulations have been done to evaluate the effectiveness of the methodology, while some are presented here to illustrate the effectiveness of the proposed algorithms for real time conflict resolution.","PeriodicalId":422463,"journal":{"name":"The 23rd Digital Avionics Systems Conference (IEEE Cat. No.04CH37576)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115434065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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