Claudine Brucks, Michael Hilker, Christoph Schommer, Cynthia Wagner, Ralph Weires
Abstract. In our understanding, a mind-map is an adaptive engine that basically works incrementally on the fundament of existing transactional streams. Generally, mind-maps consist of symbolic cells...
Hybrid Classification and Symbolic-Like Manipulation Using Self-Regulatory Feedback Networks (2009)
Kai-uwe Kühnberger, Matthew Cook, Claudine Brucks, Michael Hilker, Christoph Schommer, Cynthia Wagner, ...
The 18 th European Conference on Artificial Intelligence Proceedings 4 th International Workshop on
Georgiev, Iskren Y., Hilker, Michael, Puzia, Thomas H., Goudfrooij, Paul, Baumgardt, Holger
(Abridged) Using luminosities and structural parameters of globular clusters (GCs) in the nuclear regions (nGCs) of low-mass dwarf galaxies from HST/ACS imaging we derive the present-day escape...
Brucks, Claudine, Hilker, Michael, Schommer, Christoph, Wagner, Cynthia, Weires, Ralph
In our understanding, a mind-map is an adaptive engine that basically works incrementally on the fundament of existing transactional streams. Generally, mind-maps consist of symbolic cells that are...
Haghi, Hosein, Baumgardt, Holger, Kroupa, Pavel, Grebel, Eva K., Hilker, Michael, Jordi, Katrin
We investigate the mean velocity dispersion and the velocity dispersion profile of stellar systems in MOND, using the N-body code N-MODY, which is a particle-mesh based code with a numerical MOND...
Georgiev, Iskren Y., Puzia, Thomas H., Hilker, Michael, Goudfrooij, Paul
We investigate the old globular cluster (GC) population of 68 faint (Mv>-16 mag) dwarf galaxies located in the halo regions of nearby (
Compact stellar systems in the Fornax cluster: a UV perspective (2008)
Mieske, Steffen, Hilker, Michael, Bomans, Dominik J., Rey, Soo-Chang, Kim, Suk, Yoon, Suk-Jin, ...
In recent years, increasing evidence for chemical complexity and multiple stellar populations in massive globular clusters (GCs) has emerged, including extreme horizontal branches (EHBs) and UV...
The Nature of UCDs: Internal Dynamics from an Expanded Sample and Homogeneous Database (2008)
Mieske, Steffen, Hilker, Michael, Jordan, Andres, Infante, Leopoldo, Kissler-Patig, Markus, Rejkuba, Marina, ...
We have obtained high-resolution spectra of 23 ultra-compact dwarf galaxies (UCDs) in the Fornax cluster with -10.4>M_V>-13.5 mag (10^6
Distributed Self Management for Distributed Security Systems (2008)
Distributed system as e.g. artificial immune systems, complex adaptive systems, or multi-agent systems are widely used in Computer Science, e.g. for network security, optimisations, or simulations....
Next Challenges in Bringing Artificial Immune Systems to Production in Network Security (2008)
The human immune system protects the human body against various pathogens like e.g. biological viruses and bacteria. Artificial immune systems reuse the architecture, organization, and workflows of...
A Network Protection Framework through Artificial Immunity (2008)
Hilker, Michael, Schommer, Christoph
Current network protection systems use a collection of intelligent components - e.g. classifiers or rule-based firewall systems to detect intrusions and anomalies and to secure a network against...
SANA - Network Protection through artificial Immunity (2008)
Hilker, Michael, Schommer, Christoph
Current network protection systems use a collection of intelligent components - e.g. classifiers or rule-based firewall systems to detect intrusions and anomalies and to secure a network against...
Service Oriented Architecture in Network Security - a novel Organisation in Security Systems (2008)
Hilker, Michael, Schommer, Christoph
Current network security systems are a collection of various security components, which are directly installed in the operating system. These check the whole node for suspicious behaviour. Armouring...
SANA - Security Analysis in Internet Traffic through Artificial Immune Systems (2008)
Hilker, Michael, Schommer, Christoph
The Attacks done by Viruses, Worms, Hackers, etc. are a Network Security-Problem in many Organisations. Current Intrusion Detection Systems have significant Disadvantages, e.g. the need of plenty of...
Kayser, Andrea, Hilker, Michael, Grebel, Eva K., Willemsen, Philip G.
Our work focuses on the understanding of the origin of CNO-anomalies, which have been detected in several Galactic globular clusters (GCs). This study is based on a homogeneous data set of hundreds...
A new queueing strategy for the Adversarial Queueing Theory (2008)
Hilker, Michael, Schommer, Christoph
In the today's Internet and TCP/IP-networks, the queueing of packets is commonly implemented using the protocol FIFO (First In First Out). Unfortunately, FIFO performs poorly in the Adversarial...
AGNOSCO - Identification of Infected Nodes with artificial Ant Colonies (2008)
Hilker, Michael, Schommer, Christoph
If a computer node is infected by a virus, worm or a backdoor, then this is a security risk for the complete network structure where the node is associated. Existing Network Intrusion Detection...
Michael Hilker, Christoph Schommer, Protection System
Protects a network against intrusions Intrusions are e.g. viruses, worms, trojans, and hackers Intrusions are defined as all attacks towards a network, i.e. also intrusive behaviour from users...
Old globular clusters in magellanic-type dwarf irregular galaxies (2008)
Georgiev, Iskren Y., Goudfrooij, Paul, Puzia, Thomas H., Hilker, Michael
We present a study of the old globular clusters (GC) using archival F606W and F814W HST/ACS images of 19 Magellanic-type dwarf Irregular (dIrr) galaxies found in nearby (2 - 8 Mpc) associations of...
A flat faint end of the Fornax cluster galaxy luminosity function (2007)
Mieske, Steffen, Hilker, Michael, Infante, Leopoldo, De Oliveira, Claudia Mendes
We analyse the photometric properties of the early-type Fornax cluster dwarf galaxy population (M_V>-17 mag), based on a wide field imaging study of the central cluster area in V and I band-passes...
Siebenmorgen, Ralf, Smette, Alain, Käufl, Hans Ulrich, Seifahrt, Andreas, Uttenthaler, Stefan, Bik, Arjan, ...
• Security components Overview SANA • Security environment (2007)
Michael Hilker, Security Components
• The artificial immune system SANA is a framework to implement a distributed security system. It provides a library of non-standard approaches for security components enhanced with common-used...
Kayser, Andrea, Hilker, Michael, Richtler, Tom, Willemsen, Philip G.
Medium resolution spectra of more than 400 subgiant and turn-off region stars in Omega Centauri were analysed. The observations were performed at the VLT/Paranal with FORS2/MXU. In order to determine...
UCDs - a mixed bag of objects (2006)
The name "Ultra-Compact Dwarf Galaxy" (UCD) was invented for a new type of astronomical object that has been discovered in cores of nearby galaxy clusters a decade ago. UCDs resemble globular...
Schmid, Franz-Xaver, Vudattu, Nalini, Floerchinger, Bernhard, Hilker, Michael, Eissner, Günther, Hoenicka, Markus, ...
OBJECTIVE: We compared profiles of the numbers of circulating endothelial cells (CEC) and the apoptosis-inducing capacity of serum samples on human endothelial cells (hEC) in on-pump and off-pump...
The old globular cluster system of the dIrr galaxy NGC1427A in the Fornax cluster (2006)
Georgiev, Iskren Y., Hilker, Michael, Puzia, Thomas H., Chaname, Julio, Mieske, Steffen, Goudfrooij, Paul, ...
We present a study of the old globular cluster (GC) population of the dwarf irregular galaxy NGC 1427A using multi-wavelength VLT observations in U, B, V, I, H_alpha, J, H, and Ks bands under...
SANA - Security Analysis in Internet Traffic through Artificial Immune Systems (2006)
Hilker, Michael, Schommer, Christoph
The Attacks done by Viruses, Worms, Hackers, etc. are a Network Security-Problem in many Organisations. Current Intrusion Detection Systems have significant Disadvantages, e.g. the need of plenty of...
Some of the Galactic outer halo globular clusters are excellent tools to probe gravitational theories in the regime of weak accelerations (Baumgardt et al. 2005). The measurement of the line-of-sight...
Kinematics in Hickson Compact Group 90 (2004)
Castaneda, Leonardo, Hilker, Michael
Using long-slit spectra observed at the VLT (ESO, Paranal) in May 2002, we studied the stellar kinematics in the core of the Hickson Compact Group 90. The line of sight velocity distribution (LOSVD),...
The properties of ultra-compact dwarf galaxies and their possible origin (2004)
Hilker, Michael, Mieske, Steffen
In this contribution the discovery and properties of ultra-compact dwarf galaxies are presented, and their possible origin is discussed. This new type of galaxy resides in the cores of galaxy...
The extended star formation history of omega Centauri (2004)
Hilker, Michael, Kayser, Andrea, Richtler, Tom, Willemsen, Philip
For the first time, the abundances of a large sample of subgiant and turn-off region stars in omega Centauri have been measured, the data base being medium resolution spectroscopy from FORS2 at the...
Ultra-compact dwarf galaxies in galaxy clusters (2004)
Drinkwater, Michael J., Gregg, Michael D., Couch, Warrick J., Ferguson, Henry C., Hilker, Michael, Jones, J. Bryn, ...
We review the evidence that the ultra-compact dwarf (UCD) galaxies we recently discovered in the Fornax Cluster form a new, previously unknown class of galaxies and we discuss possible scenarios for...
Ultra-compact dwarf galaxies in galaxy clusters (2004)
Drinkwater, Michael J., Gregg, Michael D., Couch, Warrick J., Ferguson, Henry C., Hilker, Michael, Jones, J. Bryn, ...
We review the evidence that the ultra-compact dwarf (UCD) galaxies we recently discovered in the Fornax Cluster form a new, previously unknown class of galaxies and we discuss possible scenarios for...
Extragalactic Globular Clusters in the Near Infrared: III. NGC 5846 and NGC 7192 (2003)
Hempel, Maren, Hilker, Michael, Kissler-Patig, Markus, Puzia, Thomas H., Minniti, Dante, Goudfrooij, Paul
In this third paper of our series on near-IR and optical photometry of globular cluster systems in early-type galaxies we concentrate on the photometric results for NGC 5846 and NGC 7192, two group...
A class of compact dwarf galaxies from disruptive processes in galaxy clusters (2003)
Drinkwater, Michael John, Gregg, Michael D., Hilker, Michael, Bekki, Kenji, Couch, Warrick J., Ferguson,Henry C., ...
Dwarf galaxies have attracted increased attention in recent years, because of their susceptibility to galaxy transformation processes within rich galaxy clusters. Direct evidence for these processes,...
A class of compact dwarf galaxies from disruptive processes in galaxy clusters (2003)
Drinkwater, Michael John, Gregg, Michael D., Hilker, Michael, Bekki, Kenji, Couch, Warrick J., Ferguson, Henry C., ...
Dwarf galaxies have attracted increased attention in recent years, because of their susceptibility to galaxy transformation processes within rich galaxy clusters. Direct evidence for these processes,...
A class of compact dwarf galaxies from disruptive processes in galaxy clusters (2003)
Drinkwater, Michael John, Gregg, Michael D., Hilker, Michael, Bekki, Kenji, Couch, Warrick J., Ferguson, Henry C., ...
Dwarf galaxies have attracted increased attention in recent years, because of their susceptibility to galaxy transformation processes within rich galaxy clusters. Direct evidence for these processes,...
Faint dwarf spheroidals in the Fornax Cluster: A flat luminosity function (2002)
Hilker, Michael, Mieske, Steffen, Infante, Leopoldo
We have discovered about 70 very faint dwarf galaxies in the Fornax Cluster. These dSphs candidates follow the same magnitude-surface brightness relation as their counterparts in the Local Group, and...
Globular Clusters in nearby Galaxy Cluster (2002)
The discovery of a large population of intra-cluster star clusters in the central region of the Hydra I and Centaurus galaxy clusters is presented. Based on deep VLT photometry (V,I), many star...
Globular Clusters in the Central Region of Nearby Galaxy Clusters (2002)
In this contribution, first results of deep VLT photometry (V,I) in the central region of the Hydra I and Centaurus galaxy clusters are presented. In both galaxy clusters, many star clusters have...
Puzia, Thomas H., Zepf, Stephen E., Kissler-Patig, Markus, Hilker, Michael, Minniti, Dante, Goudfrooij, Paul
We combine near-infrared photometry obtained with the VLT/ISAAC instrument and archival HST/WFPC2 optical images to determine VIK magnitudes and colours of globular clusters in two early-type...
The enrichment history of omega Centauri: what we can learn from Stroemgren photometry (2002)
Hilker, Michael, Richtler, Tom
In this contribution, results from CCD vby Stroemgren photometry of a statistically complete sample of red giants and stars in the main sequence turn-off region in omega Centauri are presented. From...
Ultra Compact Objects in the Fornax Cluster of Galaxies: Globular clusters or dwarf galaxies? (2002)
Mieske, Steffen, Hilker, Michael, Infante, Leopoldo
The relation between the Ultra Compact Objects (UCOs) recently discovered in the Fornax cluster (Drinkwater et al. 2000, Hilker et al. 1999) and the brightest globular clusters associated with the...
Globular Cluster Systems in the Hydra I Galaxy Cluster (2001)
In this contribution, first results of deep VLT photometry (V,I) in the central region of the Hydra I galaxy cluster are presented. Many star clusters have been identified not only around several...
Hilker, Michael, Richtler, Tom
CCD vby Stroemgren photometry of a statistically complete sample of red giants and stars in the main sequence turn-off region in omega Centauri has been used to analyse the apparently complex star...
Revised Stroemgren metallicity calibration for red giants (1999)
A new calibration of the Stroemgren (b-y),m_1 diagram in terms of iron abundance of red giants is presented. This calibration is based on a homogeneous sample of giants in the globular clusters omega...
The center of the Fornax cluster : dwarf galaxies, cD halo, and globular clusters / (1998)
Bonn, Univ., Diss., 1998 (Nicht für den Austausch).
The globular cluster system of an ``old'' merger: NGC 5018 (1996)
Hilker, Michael, Kissler-Patig, Markus
We study the properties of the globular cluster system of the ``old'' merger NGC 5018. We detect a relatively poor globular cluster system, that can be divided into at least two populations based on...
The distance of the Fornax Cluster based on Globular Cluster Luminosity Functions (1996)
Kohle, Sven, Kissler-Patig, Markus, Hilker, Michael, Richtler, Tom, Infante, L., Quintana, H.
We present Globular Cluster Luminosity Functions for four ellipticals and one S0-Galaxy in the Fornax cluster of galaxies, derived from CCD photometry in V and I. The averaged turnover magnitudes are...