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Zuckerli: A New Compressed Representation for Graphs [article]

Luca Versari, Iulia M. Comsa, Alessio Conte, Roberto Grossi
2020 arXiv   pre-print
value of m as m · 2 j followed by l.  ...  We thus obtain each M i (x) by the following formula: M i (x) = y∈children(x) max-w (M R (y), {(x, y)} ∪ M i−1 (y)) where children(x) are the children of x in F , and max-w(A, B) returns the set of arcs  ... 
arXiv:2009.01353v1 fatcat:vfwhk6l5cvgd7jirzxeqzexoxq

Intelligent Matrix Exponentiation [article]

Thomas Fischbacher and Iulia M. Comsa and Krzysztof Potempa and Moritz Firsching and Luca Versari and Jyrki Alakuijala
2020 arXiv   pre-print
The 2-norm of the difference between the outputs can be bound as follows: ∆ o 2 ≤ S 2 exp(M + M ) − exp(M ) F ≤ ≤ √ n S 2 exp(M + M ) − exp(M ) 2 ≤ ≤ √ n S 2 M 2 exp( M 2 ) exp( M 2 ) ≤ ≤ √ n S 2 δ in  ...  An output p m is obtained as follows, using the trainable parametersS mjk andṼ m : p m =Ṽ m +S mjk exp(M ) jk (3) The matrix exp(M ), indexed by row and column indices j and k in the same way as M , is  ...  This is precisely the monomial m we started with. By the definition of the exponential of the matrix, exp(U ) then contains m (d−1)! , which is the monomial up a constant factor.  ... 
arXiv:2008.03936v1 fatcat:dj63wv43kzbfvcwphjxarxbymu

Zuckerli: A New Compressed Representation for Graphs

Luca Versari, Iulia M. Comsa, Alessio Conte, Roberto Grossi
2020 IEEE Access  
value of m as m · 2 j followed by l.  ...  We thus obtain each M i (x) by the following formula: M i (x) = y∈children(x) max-w (M R (y), {(x, y)} ∪ M i−1 (y)) where children(x) are the children of x in F , and max-w(A, B) returns the set of arcs  ... 
doi:10.1109/access.2020.3040673 fatcat:2mfppk2su5d4lns5g7uu4kbvym

Transient topographical dynamics of the electroencephalogram predict brain connectivity and behavioural responsiveness during drowsiness [article]

Iulia M Comsa, Tristan A Bekinschtein, Srivas Chennu
2017 bioRxiv   pre-print
As we fall sleep, our brain traverses a series of gradual changes at physiological, behavioural and cognitive levels, which are not yet fully understood. The loss of responsiveness is a critical event in the transition from wakefulness to sleep. Here we seek to understand the electrophysiological signatures that reflect the loss of capacity to respond to external stimuli during drowsiness using two complementary methods: spectral connectivity and EEG microstates. Furthermore, we integrate these
more » ... two methods for the first time by investigating the connectivity patterns captured during individual microstate lifetimes. While participants performed an auditory semantic classification task, we allowed them to become drowsy and unresponsive. As they stopped responding to the stimuli, we report the breakdown of frontoparietal alpha networks and the emergence of frontoparietal theta connectivity. Further, we show that the temporal dynamics of all canonical EEG microstates slow down during unresponsiveness. We identify a specific microstate (D) whose occurrence and duration are prominently increased during this period. Employing machine learning, we show that the temporal properties of microstate D, particularly its prolonged duration, predicts the response likelihood to individual stimuli. Finally, we find a novel relationship between microstates and brain networks as we show that microstate D uniquely indexes significantly stronger theta connectivity during unresponsiveness. Our findings demonstrate that the transition to unconsciousness is not linear, but rather consists of an interplay between transient brain networks reflecting different degrees of sleep depth.
doi:10.1101/231464 fatcat:m3unmqxbdfes3c7tcplk5a4peu

Transient Topographical Dynamics of the Electroencephalogram Predict Brain Connectivity and Behavioural Responsiveness During Drowsiness

Iulia M. Comsa, Tristan A. Bekinschtein, Srivas Chennu
2018 Brain Topography  
As we fall sleep, our brain traverses a series of gradual changes at physiological, behavioural and cognitive levels, which are not yet fully understood. The loss of responsiveness is a critical event in the transition from wakefulness to sleep. Here we seek to understand the electrophysiological signatures that reflect the loss of capacity to respond to external stimuli during drowsiness using two complementary methods: spectral connectivity and EEG microstates. Furthermore, we integrate these
more » ... two methods for the first time by investigating the connectivity patterns captured during individual microstate lifetimes. While participants performed an auditory semantic classification task, we allowed them to become drowsy and unresponsive. As they stopped responding to the stimuli, we report the breakdown of alpha networks and the emergence of theta connectivity. Further, we show that the temporal dynamics of all canonical EEG microstates slow down during unresponsiveness. We identify a specific microstate (D) whose occurrence and duration are prominently increased during this period. Employing machine learning, we show that the temporal properties of microstate D, particularly its prolonged duration, predicts the response likelihood to individual stimuli. Finally, we find a novel relationship between microstates and brain networks as we show that microstate D uniquely indexes significantly stronger theta connectivity during unresponsiveness. Our findings demonstrate that the transition to unconsciousness is not linear, but rather consists of an interplay between transient brain networks reflecting different degrees of sleep depth.
doi:10.1007/s10548-018-0689-9 pmid:30498872 fatcat:266kuus4evha3lbkkto64kqozq

Temporal Coding in Spiking Neural Networks with Alpha Synaptic Function: Learning with Backpropagation [article]

Iulia M. Comsa, Krzysztof Potempa, Luca Versari, Thomas Fischbacher, Andrea Gesmundo, Jyrki Alakuijala
2020 arXiv   pre-print
Given a classification problem with m inputs and n possible classes, the inputs are encoded as the spike times of individual neurons in the input layer and the result is encoded as the index of the neuron  ... 
arXiv:1907.13223v3 fatcat:y7vbsfjhsvgpbergydf6bxms5e

SO(8) supergravity and the magic of machine learning

Iulia M. Comsa, Moritz Firsching, Thomas Fischbacher
2019 Journal of High Energy Physics  
supergravity as an example, we show how modern Machine Learning software libraries such as Google's TensorFlow can be employed to greatly simplify the analysis of high-dimensional scalar sectors of some M-Theory  ...  K M AB := i 4 − ΨN Γ M AB N P Ψ P + 2 ΨM Γ B Ψ A − ΨM Γ A Ψ B + ΨB Γ M Ψ A Ω M N A := ∂ N e M A − ∂ M e N A ωMAB := ω M AB + i 4 ΨN Γ M AB N P Ψ P F M N P Q := 4δ RST U M N P Q ∂ R A ST U FMNP Q := F  ...  X F M N P Q F RST U A V W X + 3 4 • 12 2 ΨM Γ M N W XY Z Ψ N + 12 ΨW Γ XY Ψ Z F W XY Z + FW XY Z where e := det e M A D M (ω) := ∂ m − 1 4 ω M AB Γ AB , ω M AB := 1 2 (Ω ABM − Ω M AB − Ω BM A ) + K M AB  ... 
doi:10.1007/jhep08(2019)057 fatcat:zybuw7pwkzcp5gubgicld3zazq

Ecological Microclimate Influence on Grapevine Phomopsis viticola Attack Frequency in Aiud-Ciumbrud Vineyards

Sergiu SAVU, Liliana Lucia TOMOIAGA, Veronica Sanda CHEDEA
2020 Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca: Horticulture  
The infections are favored by cold and wet weather (Comsa et al., 2012) .  ...  The first symptoms appear in early spring with the growing season, when bud break is delayed (Comsa et al., 2012) (Fig. 4A ).  ... 
doi:10.15835/buasvmcn-hort:2020.0026 fatcat:d7oenci67vayhbnbqcp7c5xjva

Din însemnările profesorului Gheorghe Cantacuzino (1900–1977). III. Simpozionul neolitic organizat de Institutul de Arheologie din Bucureşti, în zilele de 30 noiembrie–2 decembrie 1972

George Trohani
2013 Cercetări Arheologice  
m Nivel II Criş 2,40-2, 70 m Nivel I Criş, sol negru mătăsos.  ...  Profesorul Gheorghe Cantacuzino notează: Stratigrafia : strat de păşune, sol de pădure, material arheologic 0-0,25 m 0,25-1,80 m straturi geologice sterile arheologic 1,80-2 m Nivel JJJ Criş 2-2,40  ... 
doi:10.46535/ca.20.10 fatcat:hddtgbalkbhwbd64adqjf5slua

Din însemnările Profesorului Gheorghe Cantacuzino (1900-1977). VI. Simpozionul de istorie şi arheologie româno-sovietic din 26-29 decembrie 1958

2018 Cercetări Arheologice  
M. Comşa susţine că cultura Dridu se întâlneşte şi în numeroase localităţi din Bulgaria, unde nu poate fi vorba de originea străromână. Trebuie pentru cultura Dridu multă prudenţă. După M.  ...  Între aceste două straturi se interpune un strat cenuşos de 0,40 m şi un strat mai negricios de 0,10 m.  construcţie arată două podele cu două cuptoare.  ... 
doi:10.46535/ca.25.10 fatcat:4onqu42tzngtnl4ybadpoojnia

Temporal Coding in Spiking Neural Networks With Alpha Synaptic Function: Learning With Backpropagation

Iulia-Maria Comsa, Krzysztof Potempa, Luca Versari, Thomas Fischbacher, Andrea Gesmundo, Jyrki Alakuijala
2021 IEEE Transactions on Neural Networks and Learning Systems  
(Corresponding author: Iulia-Maria Comşa.)  ...  Iulia-Maria Comşa, Luca Versari, Thomas Fischbacher, Andrea Gesmundo, and Jyrki Alakuijala are with Google Research Zürich, 8002 Zürich, Switzerland (e-mail: iuliacomsa@google.com; veluca@google.com; tfish  ... 
doi:10.1109/tnnls.2021.3071976 pmid:33900924 fatcat:ce6bbvtc7ze3xovswn4wioq6ei

TRANSYLVANIA AND THE OF INDO-EUROPEAN MIGRATION PROBLEM. THE ROMANIAN PARADIGM

Florin Gogâltan
2021 Lietuvos archeologija  
Comşa also undertook serious work on the topic of the westward migration of the steppe peoples (Comșa 1976; 1978; 1980; 1998; etc.) .  ...  Furthermore, 'Dans ses territoires, les débuts du processus d'«indo-européanisation» se situent à la fin du IVe millénaire' (Comșa 1998, 29) . During the same conference, M.  ... 
doi:10.33918/25386514-047009 fatcat:ei55xn4zcvbnbdd3acmbaswkyq

SITUL ARHEOLOGIC DE LA ALBA IULIA-LUMEA NOUĂ. ISTORICUL CERCETĂRILOR

Mihai Gligor
2007 Series Historica, 11/I   unpublished
Aşezarea de la Alba Iulia-Lumea Nouă a fost descoperită întâmplător în anul 1942, în urma executării unor lucrări cu caracter edilitar.  ...  Rezultatul semnificativ al acestor prime cercetări de teren constă în evidenierea în stratul de cultură, cu grosime variabilă între 0,70-2,00 m-împărit în trei niveluri-a două categorii distincte de ceramică  ...  Comşa, Cultura Boian, p. 631. 46 S.  ... 
fatcat:b5qneciq5rb2veghlmqdh2ioxi

CERCETĂRI DE SUPRAFATĂ ÎN CADRUL SITULUI NEO-ENEOLITIC DE LA CÂLNlC-"iN

Vu
unpublished
In zona M-ţilor Sebeşului se găsesc cuarţite de diferite tipuri.  ...  Comuna Cl;lnic aparţine, prin amplasarea ci, iOnei sudice a judeţului Alba, fiind situată la aproximativ 35 km. est sud-est de municipiul Alba Iulia şi la la 5 km spre sud de comuna Cut, accesul efectuându-se  ...  >clreş:i (COMŞA 1971, 15-( 9) . , In cazul de faţă utilizarea, pc lângă piesele din silex descoperite, a ce!  ... 
fatcat:zoigj6nwxzcgfgmklu2gtuc7fe

Acta Terrae Septemcastrensis, IX

Sabin Luca, Sabin Luca, Lucian Blaga, Janusz Kozłowski, Zeno-Karl Pinter, Lucian Blaga, Marin Cârciumaru, Lucian Blaga, Marius-Mihai Ciută
2010 Acta Terrae Septemcastrensis   unpublished
Ciută, Începuturile neoliticului timpuriu în spaţiul intracarpatic transilvănean, Alba Iulia, 2005. Ciută 2005a M-M.  ...  Ciută 2009a M-M.  ... 
fatcat:63wk7gxwznebvnkhpybkfqxtne
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