K. Boukouras - Academia.edu (original) (raw)

Papers by K. Boukouras

Research paper thumbnail of Seismic Waveform Data from Greece and Cyprus: Integration, Archival, and Open Access

Seismological Research Letters, 2021

The National Observatory of Athens data center for the European Integrated Data Archive (EIDA@NOA... more The National Observatory of Athens data center for the European Integrated Data Archive (EIDA@NOA) is the national and regional node that supports International Federation of Digital Seismograph Networks and related webservices for seismic waveform data coming from the southeastern Mediterranean and the Balkans. At present, it serves data from eight permanent broadband and strong-motion networks from Greece and Cyprus, individual stations from the Balkans, temporary networks and aftershock deployments, and earthquake engineering experimental facilities. EIDA@NOA provides open and unlimited access from redundant node end points, intended mainly for research purposes (see Data and Resources). Analysis and quality control of the complete seismic data archive is performed initially by calculating waveform metrics and data availability. Seismic ambient noise metrics are estimated based on power spectral densities, and an assessment of each station’s statistical mode is achieved within ea...

Research paper thumbnail of EIDA: The European Integrated Data Archive and Service Infrastructure within ORFEUS

Seismological Research Letters, 2021

The European Integrated Data Archive (EIDA) is the infrastructure that provides access to the sei... more The European Integrated Data Archive (EIDA) is the infrastructure that provides access to the seismic-waveform archives collected by European agencies. This distributed system is managed by Observatories and Research Facilities for European Seismology. EIDA provides seamless access to seismic data from 12 data archives across Europe by means of standard services, exposing data on behalf of hundreds of network operators and research organizations. More than 12,000 stations from permanent and temporary networks equipped with seismometers, accelerometers, pressure sensors, and other sensors are accessible through the EIDA federated services. A growing user base currently counting around 3000 unique users per year has been requesting data and using EIDA services. The EIDA system is designed to scale up to support additional new services, data types, and nodes. Data holdings, services, and user numbers have grown substantially since the establishment of EIDA in 2013. EIDA is currently ac...

Research paper thumbnail of The TURNkey TB4 Achaia Array: Bridging School and Citizen Seismology through Earthquake Alerting

Research paper thumbnail of Seismic Waveform Data from Greece and Cyprus: Integration, Archival, and Open Access

Seismological Research Letters

The National Observatory of Athens data center for the European Integrated Data Archive (EIDA@NOA... more The National Observatory of Athens data center for the European Integrated Data Archive (EIDA@NOA) is the national and regional node that supports International Federation of Digital Seismograph Networks and related webservices for seismic waveform data coming from the southeastern Mediterranean and the Balkans. At present, it serves data from eight permanent broadband and strong-motion networks from Greece and Cyprus, individual stations from the Balkans, temporary networks and aftershock deployments, and earthquake engineering experimental facilities. EIDA@NOA provides open and unlimited access from redundant node end points, intended mainly for research purposes (see Data and Resources). Analysis and quality control of the complete seismic data archive is performed initially by calculating waveform metrics and data availability. Seismic ambient noise metrics are estimated based on power spectral densities, and an assessment of each station’s statistical mode is achieved within ea...

Research paper thumbnail of Fabrication of midgap metal gates compatible with thin SiO2 films using low pressure chemically vapor deposited tungsten films

Research paper thumbnail of Fabrication and characteristics of midgap metal gates compatible with very thin SiO2 films using LPCVD tungsten films

Research paper thumbnail of Improving the Detectability of Seismic Events in Greece: The Rapid Deployment of Noa’s Portable Seismographic Network

A increase in the rate of the seismic activity production has been observed since the beginning o... more A increase in the rate of the seismic activity production has been observed since the beginning of 2009 to the south of Zakynthos island, in the Hellenic Arc. Three strong (Ms=6.1, 6.0 and 5.8) crustal earthquakes and thousands of smaller events have been recorded by the Hellenic National Seismographic Network which is coordinated by the Institute of Geodynamics of the National Observatory of Athens (NOA). In addition to these observations, NOA installed a newly acquired portable seismographic network in the region surrounding the seismic activity for a two month period. During this period real time data flow, from the portable seismographic network to NOA’s central data base in Athens, was accomplished using GPRS/3G lines. In this study we show that the rapid employment of NOA’s newly acquired portable seismographic network significantly improves the real-time detectability of seismic events and the assessment of seismic hazard in Greece.

Research paper thumbnail of Si etching in high-density SF6 plasmas for microfabrication: surface roughness formation

Microelectronic Engineering, 2004

Silicon etching and Si surface-roughness formation in high density SF6 plasmas was studied. Etchi... more Silicon etching and Si surface-roughness formation in high density SF6 plasmas was studied. Etching rates and surface roughness were measured and correlated with ion flux and neutral F atom flux measured in situ. Etching rates are an increasing function of F atom flux, while surface roughness is not a monotonic function of F atom flux, or the etching rate. In

Research paper thumbnail of Characteristics of W and Cu/W gate MOS diodes fabricated by a process utilizing LPCVD of W and Cu lift-off

Microelectronic Engineering, 2003

MOS diodes having double layer Cu/W, W, or Al gates were fabricated using tungsten chemical vapor... more MOS diodes having double layer Cu/W, W, or Al gates were fabricated using tungsten chemical vapor deposition, copper evaporation and lift-off and were characterized before and after thermal anneals. The breakdown field statistics were determined for all kinds of devices, while the high field conduction and charge trapping in the oxide were investigated. The W gate devices exhibited high performance

Research paper thumbnail of Si etching in high-density SF< sub> 6</sub> plasmas for microfabrication: surface roughness formation

Microelectronic …, 2004

... (a), Optical emission spectroscopy using an Acton Research SP-500 monochromator with an SBIG ... more ... (a), Optical emission spectroscopy using an Acton Research SP-500 monochromator with an SBIG CCD detector ST-6i. ... J. Vac. Sci. Technol. A, 20 2 (2002), pp. 555–563. [6] E. Gogolides, P. Vauvert, G. Kokkoris, G. Turban and A. Boudouvis. J. Appl. Phys., 88 10 (2000), p. 5570. ...

Research paper thumbnail of Towards the development of an early warning system in Greece: First results using data recorded at the HL Seismic Network

Research paper thumbnail of Aftershocks relocation and slip distribution of the 8 June 2008 (Mw 6.4) earthquake in NW Peloponnese, western Greece

On 8 June 2008 at 12:25 (GMT) a Mw 6.4 strong earthquake occurred in the area of NW Peloponnese, ... more On 8 June 2008 at 12:25 (GMT) a Mw 6.4 strong earthquake occurred in the area of NW Peloponnese, western Greece, causing the death of two people and extensive damage to the surrounding area. The main event and its aftershocks were recorded by one nationwide and three regional networks equipped with three-component broad-band seismometers. Initial locations of the earthquake sequence

Research paper thumbnail of The Hellenic Seismic Network (HL): Recent Upgrades and Developments

ABSTRACT The Institute of Geodynamics, National Observatory of Athens (NOA-IG) monitors seismicit... more ABSTRACT The Institute of Geodynamics, National Observatory of Athens (NOA-IG) monitors seismicity in Greece since its foundation in 1893. Upgrades with results towards a modernized digital seismic network started back in 2000 and they were continued since then in stages, as national funds were made available as well as more personnel was employed. The most recent upgrade started in 2007, with a dedicated project aiming to establish a Unified National Seismic Network and to link the Hellenic National Seismic Network of NOA-IG with the three Universities: Athens, Thessaloniki and Patras, which also operate local seismic networks. Although the four joining networks are operated independently, with each partner taking responsibility for the operation of its own network, the project upgrade achieved the update - improvement of every network and the seismic waveform data to be made available in near real time amongst the four partners. In parallel, a new upgraded National Strong Motion Network at NOA-IG is under way, giving the opportunity to join the continuous monitored accelerometric data in real time with the available broadband data and furthermore to upgrade existing seismic stations by deploying also an accelerometer next to the broadband sensor. Experiences through troubleshooting, methodologies and tools used to improve operation and examples of recordings from the new established infrastructure are presented, explaining the developments - improvements achieved at every stage until today. Specific earthquake recorded examples are shown, in order to explain the new possibilities opened for detail investigation and operational preparedness established on line in the 24/7 operational center at NOA-IG in Athens, as well as to other operating as backup centers. Further developments and operations using the present resulted operational - research infrastructure and the databases that are made available are also explained and presented.

Research paper thumbnail of Accessible Open Educational Resources for Students with Disabilities in Greece: They are Open to the Deaf

Lecture Notes in Computer Science, 2014

Research paper thumbnail of Rupture Process and Aftershocks Relocation of the 8 June 2008 Mw 6.4 Earthquake in Northwest Peloponnese, Western Greece

Bulletin of The Seismological Society of America, 2009

Research paper thumbnail of Routine Regional Moment Tensor Inversion for Earthquakes in the Greek Region: The National Observatory of Athens (NOA) Database (2001-2006)

Seismological Research Letters, 2010

Research paper thumbnail of Rupture Process and Aftershocks Relocation of the 8 June 2008 Mw 6.4 Earthquake in Northwest Peloponnese, Western Greece

Bulletin of the Seismological Society of America, 2009

Research paper thumbnail of Investigation of the Influence of Different Velocity Models on the Focal Mechanism Solutions Derived from Inversion of Regional Broadband Waveforms for Earthquakes in Greece

The routine use of regional broadband data for the determination of moment tensors for even very ... more The routine use of regional broadband data for the determination of moment tensors for even very small (Mw ˜ 3.5) events, has considerably enhanced our understanding of tectonic processes in many active regions around the world. However, this advance comes at the expense of having to know an adequate regional one-dimensional model that can successfully predict the source-to-receiver path effects,

Research paper thumbnail of The Hellenic Strong Seismic Motion Network: Present and near future situation and perspectives

Research paper thumbnail of The Athens Acropolis Strong Motion Array

ABSTRACT During the last decades, extensive restoration works through a dedicated &quot;Acrop... more ABSTRACT During the last decades, extensive restoration works through a dedicated &quot;Acropolis Restoration Service&quot; (YSMA) take place in the Acropolis, the greatest sanctuary of ancient Athens. Since 2008, a permanent strong motion array was deployed by the Institute of Geodynamics, National Observatory of Athens (NOA-IG) in collaboration with YSMA. Free field installations were decided at sites showing various characteristics, aiming to investigate differences in geotechnical properties as well as the structure response of Parthenon itself. The installation phase is presented, with the techniques used to overcome difficulties (i.e. extreme weather conditions, power and communication limitations, restoration works and visitors) and the special care taken for the specific archaeological site. Furthermore, indicative examples of seismic events recorded by the array are analyzed and the complexity of the hill and the monument is made apparent. Among them, the long distance events of Tohoku, Japan 2010 and Van, Turkey 2011, some regional moderate earthquakes in Greece and some weak earthquakes from the vicinity. Continuous ambient noise monitoring using PQLX software gives some first indicative results, showing a variety of characteristics at installation sites. Finally, further developments and future steps are presented such as: the extension of the array, the integration of seismic data within the GIS platform of YSMA at the site and the use of strong motion records, in conjunction with data from other monitoring systems operating in Acropolis for the study of specific monuments.

Research paper thumbnail of Seismic Waveform Data from Greece and Cyprus: Integration, Archival, and Open Access

Seismological Research Letters, 2021

The National Observatory of Athens data center for the European Integrated Data Archive (EIDA@NOA... more The National Observatory of Athens data center for the European Integrated Data Archive (EIDA@NOA) is the national and regional node that supports International Federation of Digital Seismograph Networks and related webservices for seismic waveform data coming from the southeastern Mediterranean and the Balkans. At present, it serves data from eight permanent broadband and strong-motion networks from Greece and Cyprus, individual stations from the Balkans, temporary networks and aftershock deployments, and earthquake engineering experimental facilities. EIDA@NOA provides open and unlimited access from redundant node end points, intended mainly for research purposes (see Data and Resources). Analysis and quality control of the complete seismic data archive is performed initially by calculating waveform metrics and data availability. Seismic ambient noise metrics are estimated based on power spectral densities, and an assessment of each station’s statistical mode is achieved within ea...

Research paper thumbnail of EIDA: The European Integrated Data Archive and Service Infrastructure within ORFEUS

Seismological Research Letters, 2021

The European Integrated Data Archive (EIDA) is the infrastructure that provides access to the sei... more The European Integrated Data Archive (EIDA) is the infrastructure that provides access to the seismic-waveform archives collected by European agencies. This distributed system is managed by Observatories and Research Facilities for European Seismology. EIDA provides seamless access to seismic data from 12 data archives across Europe by means of standard services, exposing data on behalf of hundreds of network operators and research organizations. More than 12,000 stations from permanent and temporary networks equipped with seismometers, accelerometers, pressure sensors, and other sensors are accessible through the EIDA federated services. A growing user base currently counting around 3000 unique users per year has been requesting data and using EIDA services. The EIDA system is designed to scale up to support additional new services, data types, and nodes. Data holdings, services, and user numbers have grown substantially since the establishment of EIDA in 2013. EIDA is currently ac...

Research paper thumbnail of The TURNkey TB4 Achaia Array: Bridging School and Citizen Seismology through Earthquake Alerting

Research paper thumbnail of Seismic Waveform Data from Greece and Cyprus: Integration, Archival, and Open Access

Seismological Research Letters

The National Observatory of Athens data center for the European Integrated Data Archive (EIDA@NOA... more The National Observatory of Athens data center for the European Integrated Data Archive (EIDA@NOA) is the national and regional node that supports International Federation of Digital Seismograph Networks and related webservices for seismic waveform data coming from the southeastern Mediterranean and the Balkans. At present, it serves data from eight permanent broadband and strong-motion networks from Greece and Cyprus, individual stations from the Balkans, temporary networks and aftershock deployments, and earthquake engineering experimental facilities. EIDA@NOA provides open and unlimited access from redundant node end points, intended mainly for research purposes (see Data and Resources). Analysis and quality control of the complete seismic data archive is performed initially by calculating waveform metrics and data availability. Seismic ambient noise metrics are estimated based on power spectral densities, and an assessment of each station’s statistical mode is achieved within ea...

Research paper thumbnail of Fabrication of midgap metal gates compatible with thin SiO2 films using low pressure chemically vapor deposited tungsten films

Research paper thumbnail of Fabrication and characteristics of midgap metal gates compatible with very thin SiO2 films using LPCVD tungsten films

Research paper thumbnail of Improving the Detectability of Seismic Events in Greece: The Rapid Deployment of Noa’s Portable Seismographic Network

A increase in the rate of the seismic activity production has been observed since the beginning o... more A increase in the rate of the seismic activity production has been observed since the beginning of 2009 to the south of Zakynthos island, in the Hellenic Arc. Three strong (Ms=6.1, 6.0 and 5.8) crustal earthquakes and thousands of smaller events have been recorded by the Hellenic National Seismographic Network which is coordinated by the Institute of Geodynamics of the National Observatory of Athens (NOA). In addition to these observations, NOA installed a newly acquired portable seismographic network in the region surrounding the seismic activity for a two month period. During this period real time data flow, from the portable seismographic network to NOA’s central data base in Athens, was accomplished using GPRS/3G lines. In this study we show that the rapid employment of NOA’s newly acquired portable seismographic network significantly improves the real-time detectability of seismic events and the assessment of seismic hazard in Greece.

Research paper thumbnail of Si etching in high-density SF6 plasmas for microfabrication: surface roughness formation

Microelectronic Engineering, 2004

Silicon etching and Si surface-roughness formation in high density SF6 plasmas was studied. Etchi... more Silicon etching and Si surface-roughness formation in high density SF6 plasmas was studied. Etching rates and surface roughness were measured and correlated with ion flux and neutral F atom flux measured in situ. Etching rates are an increasing function of F atom flux, while surface roughness is not a monotonic function of F atom flux, or the etching rate. In

Research paper thumbnail of Characteristics of W and Cu/W gate MOS diodes fabricated by a process utilizing LPCVD of W and Cu lift-off

Microelectronic Engineering, 2003

MOS diodes having double layer Cu/W, W, or Al gates were fabricated using tungsten chemical vapor... more MOS diodes having double layer Cu/W, W, or Al gates were fabricated using tungsten chemical vapor deposition, copper evaporation and lift-off and were characterized before and after thermal anneals. The breakdown field statistics were determined for all kinds of devices, while the high field conduction and charge trapping in the oxide were investigated. The W gate devices exhibited high performance

Research paper thumbnail of Si etching in high-density SF< sub> 6</sub> plasmas for microfabrication: surface roughness formation

Microelectronic …, 2004

... (a), Optical emission spectroscopy using an Acton Research SP-500 monochromator with an SBIG ... more ... (a), Optical emission spectroscopy using an Acton Research SP-500 monochromator with an SBIG CCD detector ST-6i. ... J. Vac. Sci. Technol. A, 20 2 (2002), pp. 555–563. [6] E. Gogolides, P. Vauvert, G. Kokkoris, G. Turban and A. Boudouvis. J. Appl. Phys., 88 10 (2000), p. 5570. ...

Research paper thumbnail of Towards the development of an early warning system in Greece: First results using data recorded at the HL Seismic Network

Research paper thumbnail of Aftershocks relocation and slip distribution of the 8 June 2008 (Mw 6.4) earthquake in NW Peloponnese, western Greece

On 8 June 2008 at 12:25 (GMT) a Mw 6.4 strong earthquake occurred in the area of NW Peloponnese, ... more On 8 June 2008 at 12:25 (GMT) a Mw 6.4 strong earthquake occurred in the area of NW Peloponnese, western Greece, causing the death of two people and extensive damage to the surrounding area. The main event and its aftershocks were recorded by one nationwide and three regional networks equipped with three-component broad-band seismometers. Initial locations of the earthquake sequence

Research paper thumbnail of The Hellenic Seismic Network (HL): Recent Upgrades and Developments

ABSTRACT The Institute of Geodynamics, National Observatory of Athens (NOA-IG) monitors seismicit... more ABSTRACT The Institute of Geodynamics, National Observatory of Athens (NOA-IG) monitors seismicity in Greece since its foundation in 1893. Upgrades with results towards a modernized digital seismic network started back in 2000 and they were continued since then in stages, as national funds were made available as well as more personnel was employed. The most recent upgrade started in 2007, with a dedicated project aiming to establish a Unified National Seismic Network and to link the Hellenic National Seismic Network of NOA-IG with the three Universities: Athens, Thessaloniki and Patras, which also operate local seismic networks. Although the four joining networks are operated independently, with each partner taking responsibility for the operation of its own network, the project upgrade achieved the update - improvement of every network and the seismic waveform data to be made available in near real time amongst the four partners. In parallel, a new upgraded National Strong Motion Network at NOA-IG is under way, giving the opportunity to join the continuous monitored accelerometric data in real time with the available broadband data and furthermore to upgrade existing seismic stations by deploying also an accelerometer next to the broadband sensor. Experiences through troubleshooting, methodologies and tools used to improve operation and examples of recordings from the new established infrastructure are presented, explaining the developments - improvements achieved at every stage until today. Specific earthquake recorded examples are shown, in order to explain the new possibilities opened for detail investigation and operational preparedness established on line in the 24/7 operational center at NOA-IG in Athens, as well as to other operating as backup centers. Further developments and operations using the present resulted operational - research infrastructure and the databases that are made available are also explained and presented.

Research paper thumbnail of Accessible Open Educational Resources for Students with Disabilities in Greece: They are Open to the Deaf

Lecture Notes in Computer Science, 2014

Research paper thumbnail of Rupture Process and Aftershocks Relocation of the 8 June 2008 Mw 6.4 Earthquake in Northwest Peloponnese, Western Greece

Bulletin of The Seismological Society of America, 2009

Research paper thumbnail of Routine Regional Moment Tensor Inversion for Earthquakes in the Greek Region: The National Observatory of Athens (NOA) Database (2001-2006)

Seismological Research Letters, 2010

Research paper thumbnail of Rupture Process and Aftershocks Relocation of the 8 June 2008 Mw 6.4 Earthquake in Northwest Peloponnese, Western Greece

Bulletin of the Seismological Society of America, 2009

Research paper thumbnail of Investigation of the Influence of Different Velocity Models on the Focal Mechanism Solutions Derived from Inversion of Regional Broadband Waveforms for Earthquakes in Greece

The routine use of regional broadband data for the determination of moment tensors for even very ... more The routine use of regional broadband data for the determination of moment tensors for even very small (Mw ˜ 3.5) events, has considerably enhanced our understanding of tectonic processes in many active regions around the world. However, this advance comes at the expense of having to know an adequate regional one-dimensional model that can successfully predict the source-to-receiver path effects,

Research paper thumbnail of The Hellenic Strong Seismic Motion Network: Present and near future situation and perspectives

Research paper thumbnail of The Athens Acropolis Strong Motion Array

ABSTRACT During the last decades, extensive restoration works through a dedicated &quot;Acrop... more ABSTRACT During the last decades, extensive restoration works through a dedicated &quot;Acropolis Restoration Service&quot; (YSMA) take place in the Acropolis, the greatest sanctuary of ancient Athens. Since 2008, a permanent strong motion array was deployed by the Institute of Geodynamics, National Observatory of Athens (NOA-IG) in collaboration with YSMA. Free field installations were decided at sites showing various characteristics, aiming to investigate differences in geotechnical properties as well as the structure response of Parthenon itself. The installation phase is presented, with the techniques used to overcome difficulties (i.e. extreme weather conditions, power and communication limitations, restoration works and visitors) and the special care taken for the specific archaeological site. Furthermore, indicative examples of seismic events recorded by the array are analyzed and the complexity of the hill and the monument is made apparent. Among them, the long distance events of Tohoku, Japan 2010 and Van, Turkey 2011, some regional moderate earthquakes in Greece and some weak earthquakes from the vicinity. Continuous ambient noise monitoring using PQLX software gives some first indicative results, showing a variety of characteristics at installation sites. Finally, further developments and future steps are presented such as: the extension of the array, the integration of seismic data within the GIS platform of YSMA at the site and the use of strong motion records, in conjunction with data from other monitoring systems operating in Acropolis for the study of specific monuments.