208 research outputs found
Sewer-ML: A Multi-Label Sewer Defect Classification Dataset and Benchmark
Perhaps surprisingly sewerage infrastructure is one of the most costly
infrastructures in modern society. Sewer pipes are manually inspected to
determine whether the pipes are defective. However, this process is limited by
the number of qualified inspectors and the time it takes to inspect a pipe.
Automatization of this process is therefore of high interest. So far, the
success of computer vision approaches for sewer defect classification has been
limited when compared to the success in other fields mainly due to the lack of
public datasets. To this end, in this work we present a large novel and
publicly available multi-label classification dataset for image-based sewer
defect classification called Sewer-ML.
The Sewer-ML dataset consists of 1.3 million images annotated by professional
sewer inspectors from three different utility companies across nine years.
Together with the dataset, we also present a benchmark algorithm and a novel
metric for assessing performance. The benchmark algorithm is a result of
evaluating 12 state-of-the-art algorithms, six from the sewer defect
classification domain and six from the multi-label classification domain, and
combining the best performing algorithms. The novel metric is a
class-importance weighted F2 score, , reflecting the
economic impact of each class, used together with the normal pipe F1 score,
. The benchmark algorithm achieves an
score of 55.11% and score
of 90.94%, leaving ample room for improvement on the Sewer-ML dataset. The
code, models, and dataset are available at the project page
https://vap.aau.dk/sewer-ml/Comment: CVPR 2021. Project webpage: https://vap.aau.dk/sewer-ml
Is it Raining Outside? Detection of Rainfall using General-Purpose Surveillance Cameras
In integrated surveillance systems based on visual cameras, the mitigation of
adverse weather conditions is an active research topic. Within this field, rain
removal algorithms have been developed that artificially remove rain streaks
from images or video. In order to deploy such rain removal algorithms in a
surveillance setting, one must detect if rain is present in the scene. In this
paper, we design a system for the detection of rainfall by the use of
surveillance cameras. We reimplement the former state-of-the-art method for
rain detection and compare it against a modern CNN-based method by utilizing 3D
convolutions. The two methods are evaluated on our new AAU Visual Rain Dataset
(VIRADA) that consists of 215 hours of general-purpose surveillance video from
two traffic crossings. The results show that the proposed 3D CNN outperforms
the previous state-of-the-art method by a large margin on all metrics, for both
of the traffic crossings. Finally, it is shown that the choice of
region-of-interest has a large influence on performance when trying to
generalize the investigated methods. The AAU VIRADA dataset and our
implementation of the two rain detection algorithms are publicly available at
https://bitbucket.org/aauvap/aau-virada.Comment: 10 pages, 7 figures, CVPR2019 V4AS worksho
Customer Engagement Behavior in the context of Continuous Service Relationships
This thesis discusses customers’ engagement behaviors (CEB) in the context of
continuous service relationships (telecommunication provider and financial services’
provider). CEB manifestations are agreed in literature and in business to be a potential source
of value for the firm and valuable contributions have been made, mainly focusing at
antecedents for CEB, the various CEB behaviors and consequences of CEB. Extant literature
adopts mainly a firm-centric perspective and tends to be conceptual.
This research adopts a customer-centric perspective. The methodology is qualitative and
is performed via semi-structured in-depth interviews with individuals resulting in 40 touchpoint
histories about their service relationships with their telecommunication provider and
financial services provider. Furthermore, are qualitative data collected at the
telecommunication firm, in terms of interviews with employees and participant observations
at touch-points.
CEB are definitely found to be potential sources for value-creation for the firm. CEB can
however at times destroy value or cause lost CEB value (when CEB initiatives by the firm are
not returned).
From the perspective of customers are CEB manifestations part of their everyday Life.
Customers manifest CEB to obtain a certain goal, sometimes targeted the firm, and sometimes
targeted a group external to the firm. Customers manifest CEB by adopting a certain
interaction style to facilitate goal achievement, and the way customers manifest CEB are
sometimes inconsistent and follows not necessarily pre-figured sequences.
Customers’ CEB manifestations co-exist with the experiences customers have in their
service relationships. CEB is sometimes manifested by customers to re-experience, reinforce
or challenge what the customer is currently / has been experiencing. CEB is as well
sometimes embedded in the service relationship to a degree, where customers’ experiences
and CEB become deeply intertwined or even become one and same construct, and sometimes
is a CEB manifestation a consequence of a certain customer experience.
CEB has changed the service relationship, and some of the recognized cornerstones in
what constitutes a service relationship are challenged. This thesis suggests that CEB manifestations
turn the service relationship into a plethora of (service) events of sometimes conflicting
valence, which might disrupt the value creation process intended by the firm. This might be
the reality of ‘the new service relationship’.
These obvious managerial challenges are best solved by the firm, when the firm adopts a
customer-centric approach and understands which situation(s) their customers are most
frequently in (revolving around the firm). The firm should investigate which touch-points are
relevant contingent the customer situation and finally how the touch-points could be best
possible organized to stimulate for favorable CEB. This novel managerial concept is labeled
‘customer arenas’
Presentation of Cytosolic Glycosylated Peptides by Human Class I Major Histocompatibility Complex Molecules in Vivo
Antigens presented by class I major histocompatibility complex (MHC) molecules for recognition by cytotoxic T lymphocytes consist of 8–10-amino-acid-long cytosolic peptides. It is not known whether posttranslationally modified peptides are also presented by class I MHC molecules in vivo. Many different posttranslational modifications occur on cytoplasmic proteins, including a cytosolic O-β-linked glycosylation of serine and threonine residues with N-acetylglucosamine (GlcNAc). Using synthetic glycopeptides carrying the monosaccharide O-β-GlcNAc substitution on serine residues, we have shown that glycopeptides bind efficiently to class I MHC molecules and elicit a glycopeptide-specific cytotoxic T lymphocyte response in mice. In this study, we provide evidence that peptides presented by human class I MHC molecules in vivo encompass a small, significant amount of glycopeptides, constituting up to 0.1% of total peptide. Furthermore, we find that carbohydrate structures present on glycopeptides isolated from class I MHC molecules are dominated by the cytosolic O-β-GlcNAc substitution, and synthetic peptides carrying this substitution are efficiently transported by TAP (transporter associated with antigen presentation) into the endoplasmic reticulum. Thus, in addition to unmodified peptides, posttranslationally modified cytosolic peptides carrying O-β-linked GlcNAc can be presented by class I MHC molecules to the immune system
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