The Experts below are selected from a list of 43707 Experts worldwide ranked by ideXlab platform
Gerhard Kuhn - One of the best experts on this subject based on the ideXlab platform.
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Bedform signature of a West Antarctic palaeo-ice stream reveals a multi-Temporal Record of flow and substrate control
Quaternary Science Reviews, 2009Co-Authors: Alastair G C Graham, Robert D Larter, Karsten Gohl, Claus-dieter Hillenbrand, James Smith, Gerhard KuhnAbstract:Abstract The presence of a complex bedform arrangement on the sea floor of the continental shelf in the western Amundsen Sea Embayment, West Antarctica, indicates a multi-Temporal Record of flow related to the activity of one or more ice streams in the past. Mapping and division of the bedforms into distinct landform assemblages reveals their time-transgressive history, which implies that bedforms can neither be considered part of a single downflow continuum nor a direct proxy for palaeo-ice velocity, as suggested previously. A main control on the bedform imprint is the geology of the shelf, which is divided broadly between rough bedrock on the inner shelf, and smooth, dipping sedimentary strata on the middle to outer shelf. Inner shelf bedform variability is well preserved, revealing information about local, complex basal ice conditions, meltwater flow, and ice dynamics over time. These details, which are not apparent at the scale of regional morphological studies, indicate that past ice streams flowed across the entire shelf at times, and often had onset zones that lay within the interior of the Antarctic Ice Sheet today. In contrast, highly elongated subglacial bedforms on sedimentary strata of the middle to outer shelf represent a timeslice snapshot of the last activity of ice stream flow, and may be a truer representation of fast palaeo-ice flow in these locations. A revised model for ice streams on the shelf captures complicated multi-Temporal bedform patterns associated with an Antarctic palaeo-ice stream for the first time, and confirms a strong substrate control on a major ice stream system that drained the West Antarctic Ice Sheet during the Late Quaternary.
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Bedform signature of a West Antarctic palaeo-ice stream reveals a multi-Temporal Record of flow and substrate control
Quaternary Science Reviews, 2009Co-Authors: Alastair G C Graham, Robert D Larter, Karsten Gohl, Claus-dieter Hillenbrand, James A. Smith, Gerhard KuhnAbstract:The presence of a complex bedform arrangement on the sea-floor of the continental shelf in the western Amundsen Sea Embayment, West Antarctica, indicates a multi-Temporal Record of flow related to the activity of one or more ice streams in the past. Mapping and division of the bedforms into distinct landform assemblages reveals their time-transgressive history, which implies that bedforms can neither be considered part of a single down-flow continuum nor a direct proxy for palaeo-ice velocity, as suggested previously. A main control on the bedform imprint is the geology of the shelf, which is divided broadly between rough bedrock on the inner shelf, and smooth, dipping sedimentary strata on the mid-to-outer shelf. Inner shelf bedform variability is well preserved, revealing information about local, complex basal-ice conditions, meltwater flow, and ice dynamics over time. These details, which are not apparent at the scale of regional morphological studies, indicate that past ice streams flowed across the entire shelf, at times, and often had onset zones that lay within the interior of the Antarctic Ice Sheet today. In contrast, highly elongated subglacial bedforms on sedimentary strata of the middle to outer shelf represent a timeslice snapshot of the last activity of ice-stream flow, and may be a truer representation of fast palaeo-ice flow in these locations. A revised model for ice streams on the shelf captures complicated multi-Temporal bedform patterns associated with an Antarctic palaeo-ice stream for the first time, and confirms a strong substrate control on this ice stream system that drained the West Antarctic Ice Sheet during the Late Quaternary
Alastair G C Graham - One of the best experts on this subject based on the ideXlab platform.
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Bedform signature of a West Antarctic palaeo-ice stream reveals a multi-Temporal Record of flow and substrate control
Quaternary Science Reviews, 2009Co-Authors: Alastair G C Graham, Robert D Larter, Karsten Gohl, Claus-dieter Hillenbrand, James Smith, Gerhard KuhnAbstract:Abstract The presence of a complex bedform arrangement on the sea floor of the continental shelf in the western Amundsen Sea Embayment, West Antarctica, indicates a multi-Temporal Record of flow related to the activity of one or more ice streams in the past. Mapping and division of the bedforms into distinct landform assemblages reveals their time-transgressive history, which implies that bedforms can neither be considered part of a single downflow continuum nor a direct proxy for palaeo-ice velocity, as suggested previously. A main control on the bedform imprint is the geology of the shelf, which is divided broadly between rough bedrock on the inner shelf, and smooth, dipping sedimentary strata on the middle to outer shelf. Inner shelf bedform variability is well preserved, revealing information about local, complex basal ice conditions, meltwater flow, and ice dynamics over time. These details, which are not apparent at the scale of regional morphological studies, indicate that past ice streams flowed across the entire shelf at times, and often had onset zones that lay within the interior of the Antarctic Ice Sheet today. In contrast, highly elongated subglacial bedforms on sedimentary strata of the middle to outer shelf represent a timeslice snapshot of the last activity of ice stream flow, and may be a truer representation of fast palaeo-ice flow in these locations. A revised model for ice streams on the shelf captures complicated multi-Temporal bedform patterns associated with an Antarctic palaeo-ice stream for the first time, and confirms a strong substrate control on a major ice stream system that drained the West Antarctic Ice Sheet during the Late Quaternary.
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Bedform signature of a West Antarctic palaeo-ice stream reveals a multi-Temporal Record of flow and substrate control
Quaternary Science Reviews, 2009Co-Authors: Alastair G C Graham, Robert D Larter, Karsten Gohl, Claus-dieter Hillenbrand, James A. Smith, Gerhard KuhnAbstract:The presence of a complex bedform arrangement on the sea-floor of the continental shelf in the western Amundsen Sea Embayment, West Antarctica, indicates a multi-Temporal Record of flow related to the activity of one or more ice streams in the past. Mapping and division of the bedforms into distinct landform assemblages reveals their time-transgressive history, which implies that bedforms can neither be considered part of a single down-flow continuum nor a direct proxy for palaeo-ice velocity, as suggested previously. A main control on the bedform imprint is the geology of the shelf, which is divided broadly between rough bedrock on the inner shelf, and smooth, dipping sedimentary strata on the mid-to-outer shelf. Inner shelf bedform variability is well preserved, revealing information about local, complex basal-ice conditions, meltwater flow, and ice dynamics over time. These details, which are not apparent at the scale of regional morphological studies, indicate that past ice streams flowed across the entire shelf, at times, and often had onset zones that lay within the interior of the Antarctic Ice Sheet today. In contrast, highly elongated subglacial bedforms on sedimentary strata of the middle to outer shelf represent a timeslice snapshot of the last activity of ice-stream flow, and may be a truer representation of fast palaeo-ice flow in these locations. A revised model for ice streams on the shelf captures complicated multi-Temporal bedform patterns associated with an Antarctic palaeo-ice stream for the first time, and confirms a strong substrate control on this ice stream system that drained the West Antarctic Ice Sheet during the Late Quaternary
Peter Christen - One of the best experts on this subject based on the ideXlab platform.
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A scalable privacy-preserving framework for Temporal Record linkage
Knowledge and Information Systems, 2020Co-Authors: Thilina Ranbaduge, Peter ChristenAbstract:Record linkage (RL) is the process of identifying matching Records from different databases that refer to the same entity. In many applications, it is common that the attribute values of Records that belong to the same entity evolve over time, for example people can change their surname or address. Therefore, to identify the Records that refer to the same entity over time, RL should make use of Temporal information such as the time-stamp of when a Record was created and/or update last. However, if RL needs to be conducted on information about people, due to privacy and confidentiality concerns organisations are often not willing or allowed to share sensitive data in their databases, such as personal medical Records or location and financial details, with other organisations. This paper proposes a scalable framework for privacy-preserving Temporal Record linkage that can link different databases while ensuring the privacy of sensitive data in these databases. We propose two protocols that can be used in different linkage scenarios with and without a third party. Our protocols use Bloom filter encoding which incorporates the Temporal information available in Records during the linkage process. Our approaches first securely calculate the probabilities of entities changing attribute values in their Records over a period of time. Based on these probabilities, we then generate a set of masking Bloom filters to adjust the similarities between Record pairs. We provide a theoretical analysis of the complexity and privacy of our techniques and conduct an empirical study on large real databases containing several millions of Records. The experimental results show that our approaches can achieve better linkage quality compared to non-Temporal PPRL while providing privacy to individuals in the databases that are being linked.
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privacy preserving Temporal Record linkage
International Conference on Data Mining, 2018Co-Authors: Thilina Ranbaduge, Peter ChristenAbstract:Record linkage (RL) is the process of identifying matching Records from different databases that refer to the same entity. It is common that the attribute values of Records that belong to the same entity do evolve over time, for example people can change their surname or address. Therefore, to identify the Records that refer to the same entity over time, RL should make use of Temporal information such as the time-stamp of when a Record was created and/or update last. However, if RL needs to be conducted on information about people, due to privacy and confidentiality concerns organizations are often not willing or allowed to share sensitive data in their databases, such as personal medical Records, or location and financial details, with other organizations. This paper is the first to propose a privacy-preserving Temporal Record linkage (PPTRL) protocol that can link Records across different databases while ensuring the privacy of the sensitive data in these databases. We propose a novel protocol based on Bloom filter encoding which incorporates the Temporal information available in Records during the linkage process. Our approach uses homomorphic encryption to securely calculate the probabilities of entities changing attribute values in their Records over a period of time. Based on these probabilities we generate a set of masking Bloom filters to adjust the similarities between Record pairs. We provide a theoretical analysis of the complexity and privacy of our technique and conduct an empirical study on large real databases containing several millions of Records. The experimental results show that our approach can achieve better linkage quality compared to non-Temporal PPRL while providing privacy to individuals in the databases that are being linked.
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ICDM - Privacy-Preserving Temporal Record Linkage
2018 IEEE International Conference on Data Mining (ICDM), 2018Co-Authors: Thilina Ranbaduge, Peter ChristenAbstract:Record linkage (RL) is the process of identifying matching Records from different databases that refer to the same entity. It is common that the attribute values of Records that belong to the same entity do evolve over time, for example people can change their surname or address. Therefore, to identify the Records that refer to the same entity over time, RL should make use of Temporal information such as the time-stamp of when a Record was created and/or update last. However, if RL needs to be conducted on information about people, due to privacy and confidentiality concerns organizations are often not willing or allowed to share sensitive data in their databases, such as personal medical Records, or location and financial details, with other organizations. This paper is the first to propose a privacy-preserving Temporal Record linkage (PPTRL) protocol that can link Records across different databases while ensuring the privacy of the sensitive data in these databases. We propose a novel protocol based on Bloom filter encoding which incorporates the Temporal information available in Records during the linkage process. Our approach uses homomorphic encryption to securely calculate the probabilities of entities changing attribute values in their Records over a period of time. Based on these probabilities we generate a set of masking Bloom filters to adjust the similarities between Record pairs. We provide a theoretical analysis of the complexity and privacy of our technique and conduct an empirical study on large real databases containing several millions of Records. The experimental results show that our approach can achieve better linkage quality compared to non-Temporal PPRL while providing privacy to individuals in the databases that are being linked.
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improving Temporal Record linkage using regression classification
Pacific-Asia Conference on Knowledge Discovery and Data Mining, 2017Co-Authors: Qing Wang, Dinusha Vatsalan, Peter ChristenAbstract:Temporal Record linkage is the process of identifying groups of Records that are collected over a period of time, such as in census or voter registration databases, where Records in the same group represent the same real-world entity. Such databases often contain Temporal information, such as the time when a Record was created or when it was modified. Unlike traditional Record linkage, which considers differences between Records from the same entity as errors or variations, Temporal Record linkage aims to capture Records from entities where the attribute values are known to change over time. In this paper we propose a novel approach that extends an existing Temporal approach called decay model, to categorically calculate probabilities of change for each attribute. Our novel method uses a regression-based machine learning model to predict decays for sets of attributes. Each such set of attributes has a principle attribute and support attributes, where values of the support attributes can affect the decay of the principle attribute. Our experimental results on a real US voter database show that our proposed approach results in better linkage quality compared to the decay model approach.
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PAKDD (1) - Improving Temporal Record Linkage Using Regression Classification
Advances in Knowledge Discovery and Data Mining, 2017Co-Authors: Qing Wang, Dinusha Vatsalan, Peter ChristenAbstract:Temporal Record linkage is the process of identifying groups of Records that are collected over a period of time, such as in census or voter registration databases, where Records in the same group represent the same real-world entity. Such databases often contain Temporal information, such as the time when a Record was created or when it was modified. Unlike traditional Record linkage, which considers differences between Records from the same entity as errors or variations, Temporal Record linkage aims to capture Records from entities where the attribute values are known to change over time. In this paper we propose a novel approach that extends an existing Temporal approach called decay model, to categorically calculate probabilities of change for each attribute. Our novel method uses a regression-based machine learning model to predict decays for sets of attributes. Each such set of attributes has a principle attribute and support attributes, where values of the support attributes can affect the decay of the principle attribute. Our experimental results on a real US voter database show that our proposed approach results in better linkage quality compared to the decay model approach.
Karsten Gohl - One of the best experts on this subject based on the ideXlab platform.
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Bedform signature of a West Antarctic palaeo-ice stream reveals a multi-Temporal Record of flow and substrate control
Quaternary Science Reviews, 2009Co-Authors: Alastair G C Graham, Robert D Larter, Karsten Gohl, Claus-dieter Hillenbrand, James Smith, Gerhard KuhnAbstract:Abstract The presence of a complex bedform arrangement on the sea floor of the continental shelf in the western Amundsen Sea Embayment, West Antarctica, indicates a multi-Temporal Record of flow related to the activity of one or more ice streams in the past. Mapping and division of the bedforms into distinct landform assemblages reveals their time-transgressive history, which implies that bedforms can neither be considered part of a single downflow continuum nor a direct proxy for palaeo-ice velocity, as suggested previously. A main control on the bedform imprint is the geology of the shelf, which is divided broadly between rough bedrock on the inner shelf, and smooth, dipping sedimentary strata on the middle to outer shelf. Inner shelf bedform variability is well preserved, revealing information about local, complex basal ice conditions, meltwater flow, and ice dynamics over time. These details, which are not apparent at the scale of regional morphological studies, indicate that past ice streams flowed across the entire shelf at times, and often had onset zones that lay within the interior of the Antarctic Ice Sheet today. In contrast, highly elongated subglacial bedforms on sedimentary strata of the middle to outer shelf represent a timeslice snapshot of the last activity of ice stream flow, and may be a truer representation of fast palaeo-ice flow in these locations. A revised model for ice streams on the shelf captures complicated multi-Temporal bedform patterns associated with an Antarctic palaeo-ice stream for the first time, and confirms a strong substrate control on a major ice stream system that drained the West Antarctic Ice Sheet during the Late Quaternary.
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Bedform signature of a West Antarctic palaeo-ice stream reveals a multi-Temporal Record of flow and substrate control
Quaternary Science Reviews, 2009Co-Authors: Alastair G C Graham, Robert D Larter, Karsten Gohl, Claus-dieter Hillenbrand, James A. Smith, Gerhard KuhnAbstract:The presence of a complex bedform arrangement on the sea-floor of the continental shelf in the western Amundsen Sea Embayment, West Antarctica, indicates a multi-Temporal Record of flow related to the activity of one or more ice streams in the past. Mapping and division of the bedforms into distinct landform assemblages reveals their time-transgressive history, which implies that bedforms can neither be considered part of a single down-flow continuum nor a direct proxy for palaeo-ice velocity, as suggested previously. A main control on the bedform imprint is the geology of the shelf, which is divided broadly between rough bedrock on the inner shelf, and smooth, dipping sedimentary strata on the mid-to-outer shelf. Inner shelf bedform variability is well preserved, revealing information about local, complex basal-ice conditions, meltwater flow, and ice dynamics over time. These details, which are not apparent at the scale of regional morphological studies, indicate that past ice streams flowed across the entire shelf, at times, and often had onset zones that lay within the interior of the Antarctic Ice Sheet today. In contrast, highly elongated subglacial bedforms on sedimentary strata of the middle to outer shelf represent a timeslice snapshot of the last activity of ice-stream flow, and may be a truer representation of fast palaeo-ice flow in these locations. A revised model for ice streams on the shelf captures complicated multi-Temporal bedform patterns associated with an Antarctic palaeo-ice stream for the first time, and confirms a strong substrate control on this ice stream system that drained the West Antarctic Ice Sheet during the Late Quaternary
Robert D Larter - One of the best experts on this subject based on the ideXlab platform.
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Bedform signature of a West Antarctic palaeo-ice stream reveals a multi-Temporal Record of flow and substrate control
Quaternary Science Reviews, 2009Co-Authors: Alastair G C Graham, Robert D Larter, Karsten Gohl, Claus-dieter Hillenbrand, James Smith, Gerhard KuhnAbstract:Abstract The presence of a complex bedform arrangement on the sea floor of the continental shelf in the western Amundsen Sea Embayment, West Antarctica, indicates a multi-Temporal Record of flow related to the activity of one or more ice streams in the past. Mapping and division of the bedforms into distinct landform assemblages reveals their time-transgressive history, which implies that bedforms can neither be considered part of a single downflow continuum nor a direct proxy for palaeo-ice velocity, as suggested previously. A main control on the bedform imprint is the geology of the shelf, which is divided broadly between rough bedrock on the inner shelf, and smooth, dipping sedimentary strata on the middle to outer shelf. Inner shelf bedform variability is well preserved, revealing information about local, complex basal ice conditions, meltwater flow, and ice dynamics over time. These details, which are not apparent at the scale of regional morphological studies, indicate that past ice streams flowed across the entire shelf at times, and often had onset zones that lay within the interior of the Antarctic Ice Sheet today. In contrast, highly elongated subglacial bedforms on sedimentary strata of the middle to outer shelf represent a timeslice snapshot of the last activity of ice stream flow, and may be a truer representation of fast palaeo-ice flow in these locations. A revised model for ice streams on the shelf captures complicated multi-Temporal bedform patterns associated with an Antarctic palaeo-ice stream for the first time, and confirms a strong substrate control on a major ice stream system that drained the West Antarctic Ice Sheet during the Late Quaternary.
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Bedform signature of a West Antarctic palaeo-ice stream reveals a multi-Temporal Record of flow and substrate control
Quaternary Science Reviews, 2009Co-Authors: Alastair G C Graham, Robert D Larter, Karsten Gohl, Claus-dieter Hillenbrand, James A. Smith, Gerhard KuhnAbstract:The presence of a complex bedform arrangement on the sea-floor of the continental shelf in the western Amundsen Sea Embayment, West Antarctica, indicates a multi-Temporal Record of flow related to the activity of one or more ice streams in the past. Mapping and division of the bedforms into distinct landform assemblages reveals their time-transgressive history, which implies that bedforms can neither be considered part of a single down-flow continuum nor a direct proxy for palaeo-ice velocity, as suggested previously. A main control on the bedform imprint is the geology of the shelf, which is divided broadly between rough bedrock on the inner shelf, and smooth, dipping sedimentary strata on the mid-to-outer shelf. Inner shelf bedform variability is well preserved, revealing information about local, complex basal-ice conditions, meltwater flow, and ice dynamics over time. These details, which are not apparent at the scale of regional morphological studies, indicate that past ice streams flowed across the entire shelf, at times, and often had onset zones that lay within the interior of the Antarctic Ice Sheet today. In contrast, highly elongated subglacial bedforms on sedimentary strata of the middle to outer shelf represent a timeslice snapshot of the last activity of ice-stream flow, and may be a truer representation of fast palaeo-ice flow in these locations. A revised model for ice streams on the shelf captures complicated multi-Temporal bedform patterns associated with an Antarctic palaeo-ice stream for the first time, and confirms a strong substrate control on this ice stream system that drained the West Antarctic Ice Sheet during the Late Quaternary
