1,546 research outputs found
Secure Distributed System inspired by Ant Colonies for Road Traffic Management in Emergency Situations
We have proposed an algorithm, based on ant colonies, for road traffic management. The implementation of the algorithm does not rely on fixed infrastructures in order to operate in emergency situations. It only uses the VANET
V2V communications and location systems that do not require contact with a fixed infrastructure. The algorithm uses signature aggregation and reputation lists to ensure system security. Furthermore, the algorithm has an implicit security that minimizes the risks in case of
attacks. A scale prototype has been designed and implemented to validate the algorithm using RFID location system.In this work, we present a distributed system
designed for road traffic management. The system is inspired by the behavior of the ant colonies. The distributed design responds to the particular limitations of an emergency situation; mainly, the fixed infrastructures are out of service
because no energy supply is available. The implementation is based on the VANET facilities complemented with passive RFID tags or GPS localization. The vehicles can use the
information of previous vehicles to dynamically decide the best path. A scale prototype has been developed to validate the system. It consists of several small size robotic vehicles, a test
road circuit and a visual monitorization system. The security of the system is provided by a combination of data aggregation and reputation lists.Proyecto TIN 2011-25452 (TUERI: Technologies for secUre and Efficient wiReless networks within the Internet of things with applications in transport and logistic). Y Universidad de Málaga-Campus de Excelencia Internacional Andalucia Tech
PET image classification using HHT-based features through fractal sampling
Medical image classification is currently a challenging task
that can be used to aid the diagnosis of different brain diseases. Thus,
exploratory and discriminative analysis techniques aiming to obtain rep-
resentative features from the images, play a decisive role in the design
of effective Computer Aided Diagnosis (CAD) systems, which is spe-
cially important in the early diagnosis of dementias. In this work we
present a technique that allows extracting discriminative features from
Positron Emission Tomography (PET) by means of an Empirical Mode
Decomposition-based (EEMD) method. This requires to transform the
3D PET image into a time series which is addressed by sampling the
image using a fractal-based method which allows to preserve the spa-
tial relationship among voxels. The devised technique has been used
to classify images from the Alzheimer's Disease Neuroimaging Initiat-
ive (ADNI) achieving up to a 90.5% accuracy in a differential diagnosis
task (AD vs. controls), which proves that the information retrieved by
our methodology is significantly linked to the disease.Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tech
Avoiding relapses after crises: Exploring the influence of firm investors’ characteristics on organizational resilience
Many firms may successfully navigate an organizational crisis, but may find themselves entangled in another soon
after. Building on a resource-dependence perspective, this study evaluates how certain investor characteristics foster
organizational resilience during a crisis by preventing a relapse following recovery. Drawing on data from 2014 to
2019, we analyzed 359 firms that faced a crisis in 2015, as indicated by their Altman Z-score values. Our findings reveal
that diversity and patience of investors prevent firms from relapsing into upcoming crises; however, the probability
of relapse increases when concentrated investors boost the firm’s capital during the in-crisis period. We bridge the
gap between the resource-dependence theory and literature on organizational resilience and contribute by extending
previous analyses on the relevance of investors to recover from a crisis to identify how in-crisis investors’ features also
state the foundations to avoid future relapses.Grant PID2019-
107767GA-I00 and Grant PID2022-138331NB-I00 funded by
MICIU/AEI /10.13039/501100011033ERDF/UEGrant
TED2021-129829B-I00 funded by MICIU/AEI/10.13039/5011
00011033European Union NextGenerationEU/PRTRGrant C-SEJ-069-UGR23 funded by ConsejerĂa de Universidad,
InvestigaciĂłn e InnovaciĂłnERDF Andalusia Progra
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