Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
Maria Danese*, **, Maurizio Lazzari*, Beniamino Murgante**
* National Counsil of Research Archaeological and Monumental Heritage
Institute, **Università degli Studi della Basilicata,
Dipartimento di Architettura, Pianificazione ed Infrastrutture di Trasporto
International Conference on Computational Science and Its Applications (ICCSA 2008) - 30June -3July 2008 - Perugia, Italy
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
The problem: the seismic approach
Program of prevision, prevention and protection
Seismic event consequences evaluation
and damages quantification
Analysis of seismic damage scenarios
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
Analysis of seismic damage scenarios: instruments
European Macroseismic
Macroscale 1998
Vulnerability classes
Damage levels
Historical macroseismic
scenarios
Relationships between
macroseismic intensity and damage
levels
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
Seismogeological effects
Mutual pounding of adjacent buildings
Analysis of seismic damage scenarios: limits
Factors that needs a better evaluation
“The increase in shaking due to soil amplification or topographical conditions is part of the effects that intensity is a record of, and part of the hazard to which the built environment is exposed” *
* Grünthal, G. G.: European Macroseismic Scale 1998. Conseil de l’Europe Cahiers du Centre Européen de Géodynamique et de Séisomologie, vol. 15 Luxembourg (1998)
Importance of the spatial component in seismic damage scenarios
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
Methods: the Kernel Density Estimation (KDE)
)A ..,,A ,A ,y ,(xL n21iii
n
i
issk
ss
12
)(1
)(
1)(ˆ
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
KDE: intensity“3rd dimension” of the distribution
Measure identifying event strength
Connected to the case study nature
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
KDE: intensity and its measures
First order effects(Absolute location)
Second order effects
(Relative location)
ji
ji
dsdsji dsds
dsYdsYEss
ji
))()((lim),(
0,
Properties of a spatial distribution*
*Gatrell et al. (1996)
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
KDE: kernel functions
. 1)( dxxk
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
KDE: grid resolution
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
KDE: bandwidth
Smaller Bandwidth (Levine, 1999)
Greater Bandwidth (Levine, 1999)
Relation between the bandwidth dimension and the
study area
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
KDE: bandwidth approaches
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
KDE: a method for the right choose of bandwidthNearest-Neighbor Index
rand
dNNI min n
ssd
d
n
iji
1min
min
),(
5.0n
Adran
Nearest-Neighbor Expected Distance
NNI > 1 observed distance is higher than the expected distance; events are more scattered than expected.
NNI < 1 observed distance is smaller than expected distance
Nearest-Neighbor Observed Distance
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
KDE: classification of results
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
The case of study: Potenza hilltop town1857
1930 1980
Over-consolidated clayey substratum
Sandy-conglomerate deposit lays
Narrow asymmetric
al ridge
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
The case of study: Potenza hilltop town
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
The case of study: parameters selection
Intensity choice
1. Building as autonomous scale (EMS98)
2. Relationship within buildings through reciprocal proximity and morphological factors
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
The case of study: parameters selection
Intensity choiceDamage level
Intensity in middle-southern sector Intensity in northern sector
D1 1 1
D2 2 2
D3 3 3
D4 4 5
D5 5 6
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
The case of study: parameters selection
Kernel choice
Cell size choice 0.1m
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
The case of study: parameters selection Case Bandwidth
approachMethods used to estimate t t (m) KD map
1 Fixed for whole point pattern
Nearest neighbour mean calculated for whole point pattern
6.8
Bandwidth choice
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
The case of study: parameters selection Case Bandwidth
approachMethods used to estimate t t (m) KD map
2 Two different fixed bandwidths
D1-2-3 damage level: average of building’s minimum semi-dimension.
D4-5 damage level: nearest neighbour meancalculated for whole point pattern.
3.9
6.8
Sum of two resultant raster
Bandwidth choice
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
The case of study: parameters selection Case Bandwidth
approachMethods used to estimate t t (m) KD map
3
One KDE with Fixed method, one with Adaptive method
D1-2-3 damage level: building’s minimum semi-Dimension
D4-5 damage level:Building’s area ≤ mean + sd nearest neighbour mean calculated for whole point pattern
Building’s area > mean + sd nearest neighbour mean calculated for whole point pattern multipliedby correction.
1.4÷9.9
6.8
4.1
Sum of two resultant raster
Bandwidth choice
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
Results
Maria Danese, Maurizio Lazzari, Beniamino Murgante - Maria Danese, Maurizio Lazzari, Beniamino Murgante - Kernel Density Estimation Methods for a Kernel Density Estimation Methods for a Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)Geostatistical Approach in Seismic Risk Analysis: the Case Study of Potenza Hilltop Town (southern Italy)
Conclusions and future developments•The use of geostatistics to process historical macro-seismic data is a new field of application of these techniques and represents a new approach to territorial analysis.
•Developments of the spatial analysisConsidering more parameters that can influence the result
•Fields of applicationPossibility to define urban areas historically most exposed to seismic risk, achieving useful knowledge bases for emergency planning in case of earthquakes. This work could be also a good basis for Civil Defence Plan re-examination concerning the definition of waiting and refuge areas and strategic points of entrance to old town centre.
Possibility to define monumental heritage and strategic buildings that could be most exposed to seismic risk