The Sensor Web has emerged from Earth Science research with the development of Web technology,to achieve process automation,sensor interoperation,and service synergy.These promises require the discovery of the right s...The Sensor Web has emerged from Earth Science research with the development of Web technology,to achieve process automation,sensor interoperation,and service synergy.These promises require the discovery of the right sensor at the right time and the right location with the right quality.Metadata,for sensor,platform,and data,are crucial for achieving such goals.However,analysis and practical use of these metadata reveals that the metadata and their associations are not applicable or suitable for the Sensor Web.The shortfalls are(1)the nonstandard metadata expression language;(2)the missing link between sensor and domain knowledge;(3)the insufficiency in the information for geographic locating and sensor tasking;and(4)the enhanced requirements on the quality,security,and ownership of both sensors and their sensed data.This paper reviews the current standards that have metadata components for the sensor and its platform,especially those from ISO TC211,Open Geospatial Consortium Inc.,and The National Aeronautics and Space Administration Global Change Master Directory.A recommendation on metadata that meets the requirement of crossmission sensor discovery in a pervasive Web environment is derived from them.The recommendation addresses issues on language formalization,sensor geolocation,semantics,quality,and accessibility.Roles of the emerging semantic Web technology for enabling robust discovery of sensor are discussed.展开更多
基金The study is supported in part by the NASA AIST program(Grant#NNX06AG04G,PI:Dr.Liping Di).
文摘The Sensor Web has emerged from Earth Science research with the development of Web technology,to achieve process automation,sensor interoperation,and service synergy.These promises require the discovery of the right sensor at the right time and the right location with the right quality.Metadata,for sensor,platform,and data,are crucial for achieving such goals.However,analysis and practical use of these metadata reveals that the metadata and their associations are not applicable or suitable for the Sensor Web.The shortfalls are(1)the nonstandard metadata expression language;(2)the missing link between sensor and domain knowledge;(3)the insufficiency in the information for geographic locating and sensor tasking;and(4)the enhanced requirements on the quality,security,and ownership of both sensors and their sensed data.This paper reviews the current standards that have metadata components for the sensor and its platform,especially those from ISO TC211,Open Geospatial Consortium Inc.,and The National Aeronautics and Space Administration Global Change Master Directory.A recommendation on metadata that meets the requirement of crossmission sensor discovery in a pervasive Web environment is derived from them.The recommendation addresses issues on language formalization,sensor geolocation,semantics,quality,and accessibility.Roles of the emerging semantic Web technology for enabling robust discovery of sensor are discussed.
