By Roberto Venturini - https://www.flickr.com/photos/robven/1953413479, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=57831577 1
By Roberto Venturini - - - PowerPoint PPT Presentation
By Roberto Venturini - - - PowerPoint PPT Presentation
1 By Roberto Venturini - https://www.flickr.com/photos/robven/1953413479, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=57831577 Gerrit-Jan de Bruin Supervision by Jasper van Vliet M.Sc. en dr. Johan Westerhuis Efficient compliance
Efficient compliance monitoring:
Comparison of both airborne and landside sniffing and spectrometric methods to provide direct control on the sulfur emission of ships.
Gerrit-Jan de Bruin Supervision by Jasper van Vliet M.Sc. en dr. Johan Westerhuis
Contents
Introduction Aim Analytical techniques Statistical techniques Classification with linear boundary Classification using Z-score EM algorithm Outlook
Efficient compliance monitoring 3
The emission of SO𝟑 over time.
4
50 100 150 200 250 1990 1995 2000 2005 2010 2013 2014 2015 SO₂ (kton)
SO₂ emissions in the Netherlands
Total Transport Shipping
Efficient compliance monitoring Introduction
60 000 premature deaths, Corbett 2 year loss, CAFE
5
1 2 3 4 5 01-2010 01-2012 01-2014 01-2016 01-2018 01-2020
FSC [% (m/m)]
Maximum allowed FSC
Within SECA Global
Left: Image courtesy of D.J. Oostwoud Wijdenes and National Geographic Society. Efficient compliance monitoring Introduction
$ 40 000 dayˉ¹
Fuel Sulfur Content
FSC = weight of sulphur
weight of fuel
FSC = 16 64.066×𝑁 S × SO2 − SO2 bg 𝑒𝑢 12 44×
Τ 𝑁 C 0.87 × CO2 − CO2 bg 𝑒𝑢
FSC = 0.232
SO2 − SO2 bg 𝑒𝑢 CO2 − CO2 bg 𝑒𝑢
6 Efficient compliance monitoring Introduction Image courtesy of ILT.
Aim
Compare different techniques and operators for future use for
the inspectorate.
Explore the measurements performed so far by all inspectorates
in Northern Europe.
What are the compliance rates? What are the type I and type II errors? I.e. how sure are we that
a ship is (non-)compliant?
7 Efficient compliance monitoring Introduction
8 Image courtesy: ILT Efficient compliance monitoring Introduction
9 Image courtesy: ILT Efficient compliance monitoring Introduction
TNO/ ILT sniffer
10 Efficient compliance monitoring Analytical instrument Image courtesy: ILT
BSH, 3564 Denmark, 354 DFDS-Maersk, 10 Explicit, 327 ILT, 743 MUMM, 1390 TNO, 1661
15
N = 8049
Efficient compliance monitoring Campaigns
What fraction is non-compliant?
16
200 400 600 800 2000 4000 6000 8000 < -0.1 0.1 0.2 > 0.3
FSC (% m/m) Count Cumulative count
Efficient compliance monitoring Campaigns
What fraction is non-compliant?
17
200 400 600 800 2000 4000 6000 8000 < -0.1 0.1 0.2 > 0.3
FSC (% m/m) Count Cumulative count
Efficient compliance monitoring Campaigns
What fraction is non-compliant?
18
Classification True value
7 4 6 2
N = 19 Accuracy = 47%
Efficient compliance monitoring Campaigns
Intermezzo – type I and type II errors
19
Classification True value
7 4 6 2
N = 19 Accuracy = 47% Type 1 Type 2
Efficient compliance monitoring Intermezzo
Intermezzo – type I and type II errors
20
Classification True value
7 4 6 2
N = 19 Accuracy = 47% Type 1: wrongly accusing Type 2: overlooking non-compliance
Efficient compliance monitoring Intermezzo
Intermezzo – type I and type II errors
What do we want?
21
Low type-I error High type-II error Equal type-I and type-II errors High type-I error Low type-II error Court
Efficient compliance monitoring Intermezzo
Intermezzo – type I and type II errors
What do we want?
22
Court Preselection Low type-I error High type-II error Equal type-I and type-II errors High type-I error Low type-II error
Efficient compliance monitoring Intermezzo
Intermezzo – type I and type II errors
What do we want?
23
Court Climate modeling Preselection Low type-I error High type-II error Equal type-I and type-II errors High type-I error Low type-II error
Efficient compliance monitoring Intermezzo
Intermezzo – type I and type II errors
What do we want?
24 Efficient compliance monitoring Intermezzo
Type I error Type II error
What fraction is non-compliant?
25
200 400 600 800 2000 4000 6000 8000 < -0.1 0.1 0.2 > 0.3
FSC (% m/m) Count Cumulative count
Low type II error Low type I error
Efficient compliance monitoring Campaigns
Z-score
𝐼0: The ship has a FSC of 0.1 wt. % or less. 𝐼1: The ship has a higher FSC than 0.1 wt. %. 𝑨 =
ҧ 𝑦−𝜈0 Τ 𝑡𝑦 𝑜
Z-score can be calculated to p-value with a significance level
26
N = 5552 (69%)
Efficient compliance monitoring Campaigns
Z-score with 𝜷 = 𝟏. 𝟏𝟔
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9 % 91 %
Efficient compliance monitoring Campaigns
Z-score with 𝜷 = 𝟏. 𝟏𝟔
28
Classification True value
11
4 2 2
N = 19 Accuracy = 68%
Efficient compliance monitoring Campaigns
Another approach
30 Efficient compliance monitoring Another approach
What fraction is non-compliant?
31
How many port state controls should take place? How reliable are climate modellings assuming 100% compliance? What is the catch rate?
Efficient compliance monitoring Another approach
EM-algorithm
32 Efficient compliance monitoring Another approach
EM algorithm
Guess initial parameters Calculate responsibility Maximize likelihood of all parameters
33 Efficient compliance monitoring Another approach
34
𝛿𝑗,0 = 1 𝛿𝑗,1 = 0 𝛿𝑗,0 = 0.5 𝛿𝑗,1 = 0.5 𝛿𝑗,0 = 0 𝛿𝑗,1 = 1
𝛿𝑗,0 + 𝛿𝑗,1 = 1 For each datapoint i
Efficient compliance monitoring Another approach
EM algorithm
Guess initial parameters Calculate responsibility Maximize likelihood of all parameters
ෞ 𝜈𝑙 = 1 𝑜𝑙
𝑗∈𝑙 𝑜𝑙
𝑦𝑗 ෞ 𝜏𝑙 = 1 𝑜𝑙
𝑗∈𝑙 𝑜𝑙
𝑦𝑗 − 𝜈𝑙 2
35 Efficient compliance monitoring Another approach
EM algorithm
Guess initial parameters Calculate responsibility Maximize likelihood of all parameters
ෞ 𝜈𝑙 = 1 𝑜𝑙
𝑗∈𝑙 𝑜𝑙
𝑦𝑗 ෞ 𝜏𝑙 = 1 𝑜𝑙
𝑗∈𝑙 𝑜𝑙
𝑦𝑗 − 𝜈𝑙 2
36 Efficient compliance monitoring Another approach
EM algorithm
Guess initial parameters Calculate responsibility Maximize likelihood of all parameters
Iterate until convergence
37 Efficient compliance monitoring Another approach
EM-algorithm
38
N = 5552 (69%) 𝜈1 = 0.06 wt−% 𝜏1 = 0.04 wt−% 𝜈2 = −1.1 wt−% 𝜏2 = 0.8 wt−%
96 % 4 %
Efficient compliance monitoring Another approach
What fraction is non-compliant?
39
200 400 600 800 2000 4000 6000 8000 < -0.1 0.1 0.2 > 0.3
FSC (% m/m) Count Cumulative count
Efficient compliance monitoring Another approach
EM algorithm
Guess initial parameters Calculate responsibility
ෞ 𝛿𝑗,𝑙 = ฏ 𝜌𝑙 prior 𝒪(𝑦𝑗| ෞ 𝜈𝑙, ෞ 𝜏𝑙
2)
likelihood 𝜌1𝒪(𝑦𝑗| ෞ 𝜈1, ෞ 𝜏1
2) + 𝜌2Lognormal(𝑦𝑗 − 0.1| ෞ
𝜈2, ෞ 𝜏2
2)
evidence
Maximize likelihood
40 Efficient compliance monitoring Another approach
ෞ 𝜈𝑑 = σ𝑗∈𝑑
𝑜𝑙 𝑦𝑗
𝑂𝑑 ෞ 𝜏𝑑 = σ𝑗∈𝑑
𝑜𝑙 𝑦𝑗 − 𝜈𝑑 2
𝑂𝑑
Type your footer here 41
ෞ 𝜈𝑜𝑑 = 1 𝑂𝑜𝑑
𝑗∈𝑜𝑑 𝑜𝑙
log 𝑦𝑗 − 0.1 ෞ 𝜏𝑜𝑑 = 1 𝑂𝑜𝑑
𝑗∈𝑜𝑑 𝑜𝑙
log 𝑦𝑗 − 0.1 − 𝜈𝑜𝑑 2
42 Efficient compliance monitoring Another approach
43
3 % 97 %
Efficient compliance monitoring Another approach
Outlook
Determine the relation between type I and type II errors more
precisely.
Better instruments will result in better accuracy. Better validation makes the introduction of supervised methods
possible.
44 Efficient compliance monitoring Outlook