Pub Date : 1998-07-13DOI: 10.1109/NAECON.1998.710131
G. Tolometti, V. Sannders
A collaborative enterprise environment is an application of advanced distributed simulation and information technology in an integrated environment to support technology development, system design, performance, cost, and producibility trade-off analyses throughout the entire product and system engineering life cycle. The Sensors and Information Directorates, Air Force Research Laboratory (AFRL) have initiated a major effort to implement a Collaborative Environment (CE) to provide the framework and development methodology required for affordable and timely technology for the 21/sup st/ Century warfighter. This paper discusses AFRL's efforts to support the new Air Force vision and to maximize its internal business processes through enterprise-wide cooperation. The paper discusses the need for a CE as a result of Acquisition Reform and Simulation-based Acquisition; describes CE and how the framework supports enterprise-wide collaboration of multidisciplinary expertise; and describes a CE technical architecture and the new technologies that distinguish it from conventional distributed processing systems.
{"title":"An Air Force collaborative enterprise environment","authors":"G. Tolometti, V. Sannders","doi":"10.1109/NAECON.1998.710131","DOIUrl":"https://doi.org/10.1109/NAECON.1998.710131","url":null,"abstract":"A collaborative enterprise environment is an application of advanced distributed simulation and information technology in an integrated environment to support technology development, system design, performance, cost, and producibility trade-off analyses throughout the entire product and system engineering life cycle. The Sensors and Information Directorates, Air Force Research Laboratory (AFRL) have initiated a major effort to implement a Collaborative Environment (CE) to provide the framework and development methodology required for affordable and timely technology for the 21/sup st/ Century warfighter. This paper discusses AFRL's efforts to support the new Air Force vision and to maximize its internal business processes through enterprise-wide cooperation. The paper discusses the need for a CE as a result of Acquisition Reform and Simulation-based Acquisition; describes CE and how the framework supports enterprise-wide collaboration of multidisciplinary expertise; and describes a CE technical architecture and the new technologies that distinguish it from conventional distributed processing systems.","PeriodicalId":202280,"journal":{"name":"Proceedings of the IEEE 1998 National Aerospace and Electronics Conference. NAECON 1998. Celebrating 50 Years (Cat. No.98CH36185)","volume":"49 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120993133","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 : 1998-07-13DOI: 10.1109/NAECON.1998.710149
Tao Huamin, Zhang Zhiqun
In this paper, characteristic polarizations are used to describe the stability properties of target's spatial polarization structure in optics region on the wideband polarimetric radar. On this basis, polarization features are extracted to classify four kinds of aircraft. Recognition results show that these features are insensitive to target's posture to a great extent and this method based on characteristic polarization is effective and feasible.
{"title":"Target recognition based on characteristic polarizations, in the optics region","authors":"Tao Huamin, Zhang Zhiqun","doi":"10.1109/NAECON.1998.710149","DOIUrl":"https://doi.org/10.1109/NAECON.1998.710149","url":null,"abstract":"In this paper, characteristic polarizations are used to describe the stability properties of target's spatial polarization structure in optics region on the wideband polarimetric radar. On this basis, polarization features are extracted to classify four kinds of aircraft. Recognition results show that these features are insensitive to target's posture to a great extent and this method based on characteristic polarization is effective and feasible.","PeriodicalId":202280,"journal":{"name":"Proceedings of the IEEE 1998 National Aerospace and Electronics Conference. NAECON 1998. Celebrating 50 Years (Cat. No.98CH36185)","volume":"09 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127201601","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 : 1998-07-13DOI: 10.1109/NAECON.1998.710154
L. Concha, B. C. Read, D. Bawcom, P. Jarusewic, B. Kadrovach, K. Pedersen
As defense budgets continue to shrink the Air Force needs an improved method for procurement of weapons electronics systems. We propose strengthening the front end to the procurement process by allowing the users to try out their ideas before committing to a lengthy and expensive procurement cycle. Modeling and Simulation (M&S) shows great promise as a tool to achieve cost effective and requirements focused procurement. Procurers need a simulatable model to allow their users to test a virtual version of their procurement specifications. This paper presents an example of using a VHDL model, documentation, and associated test vectors as a "procurement specification".
{"title":"Simulation based design of the monobit receiver","authors":"L. Concha, B. C. Read, D. Bawcom, P. Jarusewic, B. Kadrovach, K. Pedersen","doi":"10.1109/NAECON.1998.710154","DOIUrl":"https://doi.org/10.1109/NAECON.1998.710154","url":null,"abstract":"As defense budgets continue to shrink the Air Force needs an improved method for procurement of weapons electronics systems. We propose strengthening the front end to the procurement process by allowing the users to try out their ideas before committing to a lengthy and expensive procurement cycle. Modeling and Simulation (M&S) shows great promise as a tool to achieve cost effective and requirements focused procurement. Procurers need a simulatable model to allow their users to test a virtual version of their procurement specifications. This paper presents an example of using a VHDL model, documentation, and associated test vectors as a \"procurement specification\".","PeriodicalId":202280,"journal":{"name":"Proceedings of the IEEE 1998 National Aerospace and Electronics Conference. NAECON 1998. Celebrating 50 Years (Cat. No.98CH36185)","volume":"2 9","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113960128","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 : 1998-07-13DOI: 10.1109/NAECON.1998.710145
J. See, I. Davis, G. Kuperman
The present study examined automatic target cueing (ATC) and target localization performance using realistic synthetic aperture radar (SAR) imagery presented in either an unaided or aided format. After viewing each SAR patch map, participants identified the location of the target, a transporter-erector-launcher (TEL), and rated their confidence in that decision. Overall, ATC cueing enhanced operators' confidence in their decision making but did not alter their localization accuracy, perceptual sensitivity (d'), or speed relative to the unaided condition. Further analysis revealed, however, that a critical determinant of operator performance and confidence was the "reliability" of the ATC. If all of the ATC's cues were false alarms, performance was worse than if no aiding had been provided at all. On the other hand, performance was most effective when the majority of the cues were centered over man-made vehicles.
{"title":"Aided and unaided operator performance with synthetic aperture radar imagery","authors":"J. See, I. Davis, G. Kuperman","doi":"10.1109/NAECON.1998.710145","DOIUrl":"https://doi.org/10.1109/NAECON.1998.710145","url":null,"abstract":"The present study examined automatic target cueing (ATC) and target localization performance using realistic synthetic aperture radar (SAR) imagery presented in either an unaided or aided format. After viewing each SAR patch map, participants identified the location of the target, a transporter-erector-launcher (TEL), and rated their confidence in that decision. Overall, ATC cueing enhanced operators' confidence in their decision making but did not alter their localization accuracy, perceptual sensitivity (d'), or speed relative to the unaided condition. Further analysis revealed, however, that a critical determinant of operator performance and confidence was the \"reliability\" of the ATC. If all of the ATC's cues were false alarms, performance was worse than if no aiding had been provided at all. On the other hand, performance was most effective when the majority of the cues were centered over man-made vehicles.","PeriodicalId":202280,"journal":{"name":"Proceedings of the IEEE 1998 National Aerospace and Electronics Conference. NAECON 1998. Celebrating 50 Years (Cat. No.98CH36185)","volume":"213 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132289803","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 : 1998-07-13DOI: 10.1109/NAECON.1998.710112
G. Fitzhugh
In 1993, the Office of Naval Research (ONR), in conjunction with the Undersecretary of the Navy for Research, Development, and Acquisition established a program known as Technology for Affordability. That program is executed today in many of the Navy's weapon systems procurements and is specifically resident in two ONR programs: Manufacturing Technology and Small Business Innovation Research (SBIR). The technology discussed in this paper was developed under the auspices of the SBIR program and is known as Rapid Retargeting. It is executed through VisiCom Laboratories, Inc., a California-based small business. Rapid Retargeting rehosts existing logic into new hardware technology. This rehosting process begins by extracting the functionality of the target hardware and capturing it in VHSIC Hardware Descriptive Language (VHDL). The resulting software models are simulated and compared with the original hardware for verification. Once verified the models are ported to a new hardware design. Subsequently, parts obsolescence is no longer an issue: software models can be rehosted whenever new technology becomes available.
{"title":"Rapid retargeting a solution to electronic systems obsolescence","authors":"G. Fitzhugh","doi":"10.1109/NAECON.1998.710112","DOIUrl":"https://doi.org/10.1109/NAECON.1998.710112","url":null,"abstract":"In 1993, the Office of Naval Research (ONR), in conjunction with the Undersecretary of the Navy for Research, Development, and Acquisition established a program known as Technology for Affordability. That program is executed today in many of the Navy's weapon systems procurements and is specifically resident in two ONR programs: Manufacturing Technology and Small Business Innovation Research (SBIR). The technology discussed in this paper was developed under the auspices of the SBIR program and is known as Rapid Retargeting. It is executed through VisiCom Laboratories, Inc., a California-based small business. Rapid Retargeting rehosts existing logic into new hardware technology. This rehosting process begins by extracting the functionality of the target hardware and capturing it in VHSIC Hardware Descriptive Language (VHDL). The resulting software models are simulated and compared with the original hardware for verification. Once verified the models are ported to a new hardware design. Subsequently, parts obsolescence is no longer an issue: software models can be rehosted whenever new technology becomes available.","PeriodicalId":202280,"journal":{"name":"Proceedings of the IEEE 1998 National Aerospace and Electronics Conference. NAECON 1998. Celebrating 50 Years (Cat. No.98CH36185)","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132370851","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 : 1998-07-13DOI: 10.1109/NAECON.1998.710140
S.J. Asseo
In-flight replanning of a strike mission requires the capability of generating survivable penetration routes, quickly and efficiently, with limited computer resources on board the aircraft. Although dynamic programming (DP) has been used traditionally for route generation, it requires quantization of the state space into cells of specified dimensions, and places restrictions on the route to traverse the state space from cell center to cell center along one of the prescribed headings. The algorithm developed avoids threat zones of circular shapes, and is ideal for in-flight replanning of penetration routes. The algorithm is much faster than DP, it generates flyable routes that do not require smoothing, and the run time depends strictly on the number of threats to be avoided, rather than on cell size used for state space quantization. The algorithm uses geometric construction to synthesize routes with linear segments tangent to the threat periphery and circular segments along the threat periphery, and obtains the shortest route between a starting point and a destination point, by using the principle of optimality. The algorithm is validated in a high density threat environment with overlapping threat lethality envelopes of varying sizes, and used to generate various penetration routes.
{"title":"In-flight replanning of penetration routes to avoid threat zones of circular shapes","authors":"S.J. Asseo","doi":"10.1109/NAECON.1998.710140","DOIUrl":"https://doi.org/10.1109/NAECON.1998.710140","url":null,"abstract":"In-flight replanning of a strike mission requires the capability of generating survivable penetration routes, quickly and efficiently, with limited computer resources on board the aircraft. Although dynamic programming (DP) has been used traditionally for route generation, it requires quantization of the state space into cells of specified dimensions, and places restrictions on the route to traverse the state space from cell center to cell center along one of the prescribed headings. The algorithm developed avoids threat zones of circular shapes, and is ideal for in-flight replanning of penetration routes. The algorithm is much faster than DP, it generates flyable routes that do not require smoothing, and the run time depends strictly on the number of threats to be avoided, rather than on cell size used for state space quantization. The algorithm uses geometric construction to synthesize routes with linear segments tangent to the threat periphery and circular segments along the threat periphery, and obtains the shortest route between a starting point and a destination point, by using the principle of optimality. The algorithm is validated in a high density threat environment with overlapping threat lethality envelopes of varying sizes, and used to generate various penetration routes.","PeriodicalId":202280,"journal":{"name":"Proceedings of the IEEE 1998 National Aerospace and Electronics Conference. NAECON 1998. Celebrating 50 Years (Cat. No.98CH36185)","volume":"205 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131768195","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 : 1998-07-13DOI: 10.1109/NAECON.1998.710109
D.W. Brayman, G. Al-Salechi, F. Scarpino
As digital systems grow rapidly in complexity and sophistication, the educational process must provide future developers with experience that incorporates advanced development tools and modem design techniques. However, this cannot be achieved at the expense of relevant theory and traditional design methods on which modem methods are based. Hence, the learning experience must efficiently combine emphasis on classical design principles with an exposure to state-of-the-art tools and techniques. This student project demonstrates the use of hardware description language design with programmable logic devices to develop a digital system of significant complexity, while introducing the basic principles of spread spectrum communications. After 20 years, this latter technology still remains a modern digital approach to reliable communications, and provides a practical and challenging educational application. This paper summarizes the design and full system hardware implementation of a baseband digital direct sequence spread spectrum communication system for classroom demonstration. The system configuration includes a serial transmitter with pseudorandom spreading routine, a receiver with despreader, and other diagnostic equipment.
{"title":"A direct sequence baseband communications system using programmable logic devices","authors":"D.W. Brayman, G. Al-Salechi, F. Scarpino","doi":"10.1109/NAECON.1998.710109","DOIUrl":"https://doi.org/10.1109/NAECON.1998.710109","url":null,"abstract":"As digital systems grow rapidly in complexity and sophistication, the educational process must provide future developers with experience that incorporates advanced development tools and modem design techniques. However, this cannot be achieved at the expense of relevant theory and traditional design methods on which modem methods are based. Hence, the learning experience must efficiently combine emphasis on classical design principles with an exposure to state-of-the-art tools and techniques. This student project demonstrates the use of hardware description language design with programmable logic devices to develop a digital system of significant complexity, while introducing the basic principles of spread spectrum communications. After 20 years, this latter technology still remains a modern digital approach to reliable communications, and provides a practical and challenging educational application. This paper summarizes the design and full system hardware implementation of a baseband digital direct sequence spread spectrum communication system for classroom demonstration. The system configuration includes a serial transmitter with pseudorandom spreading routine, a receiver with despreader, and other diagnostic equipment.","PeriodicalId":202280,"journal":{"name":"Proceedings of the IEEE 1998 National Aerospace and Electronics Conference. NAECON 1998. Celebrating 50 Years (Cat. No.98CH36185)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128719762","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 : 1998-07-13DOI: 10.1109/NAECON.1998.710203
R. Baucom, T. A. DeLong, D.T. Smith, B.W. Johnson, J. Hanna
There is a need for simulator-independent, VHDL-based fault simulation. Existing techniques for VHDL-based fault simulation are reviewed. Robust, a simulator-independent fault simulator tool, is described. Slow simulation speed is identified as one limitation of the current Robust tool and distributed simulation on a network of workstations is identified as a feasible way to improve its performance. Previous network-of-workstations fault simulation experiments are reviewed. Current efforts to enhance the Robust tool using SAVANT ate described. A system using Robust (with SAVANT extensions) for fault simulation on a network of workstations is proposed, using the TyVIS VHDL simulation kernel and the Legion distributed processing system.
{"title":"VHDL-based distributed fault simulation using SAVANT","authors":"R. Baucom, T. A. DeLong, D.T. Smith, B.W. Johnson, J. Hanna","doi":"10.1109/NAECON.1998.710203","DOIUrl":"https://doi.org/10.1109/NAECON.1998.710203","url":null,"abstract":"There is a need for simulator-independent, VHDL-based fault simulation. Existing techniques for VHDL-based fault simulation are reviewed. Robust, a simulator-independent fault simulator tool, is described. Slow simulation speed is identified as one limitation of the current Robust tool and distributed simulation on a network of workstations is identified as a feasible way to improve its performance. Previous network-of-workstations fault simulation experiments are reviewed. Current efforts to enhance the Robust tool using SAVANT ate described. A system using Robust (with SAVANT extensions) for fault simulation on a network of workstations is proposed, using the TyVIS VHDL simulation kernel and the Legion distributed processing system.","PeriodicalId":202280,"journal":{"name":"Proceedings of the IEEE 1998 National Aerospace and Electronics Conference. NAECON 1998. Celebrating 50 Years (Cat. No.98CH36185)","volume":"149 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114420931","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 : 1998-07-13DOI: 10.1109/NAECON.1998.710128
J. Montgomery, R. Sanderson, B. L. Clinton, F. Baxley
Two-color mid-infrared background measurements of terrain were completed in the fall of 1997. The data was collected using a 256/spl times/256 InSb sensor with optimized two color filter wheel integrated with the optics. This configuration allowed the collection of temporally correlated, radiometrically calibrated data in two spectral bands that was compared to background imagery taken with a different sensor in the summer of 1996. The data collections were taken from a modified Cessna 172 at medium and low altitudes. The new sensor possesses higher spatial resolution, greater sensitivity, larger field of regard, and optimized spectral bands to provide excellent capability for collection of meaningful phenomenological data. The data was analyzed to assess the new inter-band correlation and compared to collections made last year with an earlier sensor. Analysis of the collected data using embedded targets was accomplished in order to characterize the discrimination potential of the modified bands.
{"title":"Characterization of two color mid-infrared measurements","authors":"J. Montgomery, R. Sanderson, B. L. Clinton, F. Baxley","doi":"10.1109/NAECON.1998.710128","DOIUrl":"https://doi.org/10.1109/NAECON.1998.710128","url":null,"abstract":"Two-color mid-infrared background measurements of terrain were completed in the fall of 1997. The data was collected using a 256/spl times/256 InSb sensor with optimized two color filter wheel integrated with the optics. This configuration allowed the collection of temporally correlated, radiometrically calibrated data in two spectral bands that was compared to background imagery taken with a different sensor in the summer of 1996. The data collections were taken from a modified Cessna 172 at medium and low altitudes. The new sensor possesses higher spatial resolution, greater sensitivity, larger field of regard, and optimized spectral bands to provide excellent capability for collection of meaningful phenomenological data. The data was analyzed to assess the new inter-band correlation and compared to collections made last year with an earlier sensor. Analysis of the collected data using embedded targets was accomplished in order to characterize the discrimination potential of the modified bands.","PeriodicalId":202280,"journal":{"name":"Proceedings of the IEEE 1998 National Aerospace and Electronics Conference. NAECON 1998. Celebrating 50 Years (Cat. No.98CH36185)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127681730","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 : 1998-07-13DOI: 10.1109/NAECON.1998.710202
J. Willis, G. D. Peterson, S. Gregor
Today's electronic system designers are faced with steadily increasing pressures to deliver greater functionality at less cost in less time. The Advanced Intermediate Representation with Extensibility/Common Environment, AIRE/CE, addresses these pressures by providing fundamentally new capability to both integrate state-of-the-art tool components into a program's design now and exchange partially compiled hardware/system designs.
{"title":"The advanced intermediate representation with extensibility/common environment (AIRE/CE)","authors":"J. Willis, G. D. Peterson, S. Gregor","doi":"10.1109/NAECON.1998.710202","DOIUrl":"https://doi.org/10.1109/NAECON.1998.710202","url":null,"abstract":"Today's electronic system designers are faced with steadily increasing pressures to deliver greater functionality at less cost in less time. The Advanced Intermediate Representation with Extensibility/Common Environment, AIRE/CE, addresses these pressures by providing fundamentally new capability to both integrate state-of-the-art tool components into a program's design now and exchange partially compiled hardware/system designs.","PeriodicalId":202280,"journal":{"name":"Proceedings of the IEEE 1998 National Aerospace and Electronics Conference. NAECON 1998. Celebrating 50 Years (Cat. No.98CH36185)","volume":"96 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125984528","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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